With corrs (or their heroic counterparts: Defenders) I always seem to look to IO slot for recharge in set bonuses.
As far as which choice to go with? Sonic/Kin will be fast paced, living on a knife's edge, kinda play style, since you'll be reliant on heals (that need to hit) to survive. Should be exciting I'd say.
Sonic/Pain, honestly sounds like a sweet combination, thought my opinion of World of Pain is that, while it is a nice buff, isn't anything spectacular, so it wouldn't be the crutch you want. I love soothing aura though.
Sonic/Cold is completely devastating to all it encounters. Heat loss has a 6 minute recharge I believe...so huffing it out without stamina between recharges would be rough, unless you slot extensively for +end and +recovery IOs. So, it's possible, but getting to level 38 without it would be a struggle. The problem with this combo for soloing early on, is lack of any healing for yourself, and sonic's lack of doing anything but damage early on(very early on).
Anything you pick will be fun, but I can honestly say, I've vote for either sonic/pain or sonic/cold, since I never liked the feel of Kin (personal opinion!) (though fulcrum shift is sweeeeet).
If you do roll up a sonic/pain...tell me how it is, my only pain char is AR/Pain, and I can tell you, that combination is weird.
Anyway, I'm straying from the topic...I'd say pick one and have fun! and if you can get a team consistently...you're doing better than I ever do in Villains 
My Sonic/Kin (now 50) is ridiculously easy, the easiest of any Corruptor, blaster, or defender I've ever played.
Solo missions - I Siren's Song, everybody is asleep, if not then I Shout the one who isn't. Then I Siphon Speed, Siphon Sower, then Shout the one I want to kill first (if I haven't already), then chain st attack, meanwhile you kill group after group and none of them have even attacked you. Rinse and repeat. I often will take *no* damage an entire mission. You can do this from 28 on, and I've often wondered if it was even worth it to siphon.
Before Shout (28) it's a little more difficult, but you get to sleep everybody and siphon them before you even take an attack. So you are faster and stronger, and they are weaker and slower right from the get go. You have to intersperse some heals as needed.
Before Siren's Song (18) it's considerably harder, but you've still got good st damage and the -resists from each to help out, and the heal.
My one and only complaint about the set is I wish the nuke didn't drain all your end. That's a real *****, all your toggles go down and you are vulnerable. Hopefully you stunned everything, except bosses+, who are going to chew you a new one. You have to either wait or pop a blue and hope your transference hits something still standing. Then you get to go through and turn all your toggles back on. I've found at 50 it's not really worth the time it takes to recover from nuking, so I don't.
I also still find stamina really really helpful, even with it I still have to transference once in awhile I'd rather be doing something more effective. You could try living without it, but whenever you are fighting something and transference doesn't hit, you'll be hatting life, and probably quickly dying. Also you won't be getting transference until 35, so that's 15 levels between when you should have got stamina and transference you'll be really hurting. You don't really need anything else anyway, you've got room enough for it without skipping anything you might otherwise need. I mean sure you could get leadership, but those use up a lot of endurance, so you need stamina to run them anyway.
One thing I don't really see the need for is expensive recharge sets and IOs, which is really nice. I haven't really done anything with sets, i've just got stuff with 50 IOs and some frankenslotting, and I keep wondering what I should do, I'm guessing I'll go for defense stuff if I can figure it out.
I tried playing various kins and just hated them, rad/kin (no mitigation, so dies like a mayfly), a fire/kin controller(not enough damage early, couldn't tough it out). I tired a couple other sonics too - a sonic/dark and a sonic/sonic neither of those seemed to work very well for me.
Sonic blast is pretty much always survivable, so it really depends on what your playstyle is for which secondary you want.
I can't comment on /pain, never having played it myself, but my friends who do seem to like it ok.
Sonic/Cold would be a solid combination, and most likely the AV killer once it gets into its own. Only downside is /cold is slow to get really good. Upside is...once it's good, it's good. And heat loss really isn't good enough to replace stamina. Also, you get it at 38 (I think), and that's a very, very, very long time with low recharge rate. Add in the fact both sonic and cold are end happy builds....probably not a wise idea. Perhaps with an eye to +recovery in IO slotting it'd be manageable, but I don't think it'd be overly fun. But /cold as a whole is a fun, really powerful build, either solo or team.
Sonic/Kin would be a fun combination, but as justisaur said, it'll be rough til Siren's. Transference should be enough to keep you going once you get it (just slot it with a combination of acc, recharge and end mod), but you may want to pick up Stamina until then, and then respec out of Stamina once you get to 35. Sonic would be one of the more survivable kin combos, but even with siren's song and (if you want it), the stun, kin is still something of a knife's blade playing style, so it takes a bit of getting used to...
Given what you said you wanted...I'd probably recommend sonic/cold. It's a bit more balanced in terms of what it can do, and you should be able to easily kill most EBs solo with it. Sonic/kin would be fun, but a lot harder on EBs, and it can be a lot harder to solo with a kin through a couple level stretches (the 30's are harsh, if I remember correctly).
Can't really talk about IOs much, I let my friends who enjoy number crunching tweak my builds if I decide to use them.
Completely agree with justisaur, from a Defender's PoV. Siren's gives you the time to set up Fulcrum, Screech lets you wake them up one by one (and carries the -res too) and then you just blast single target. Easy peasy. If you're going to nuke and there is a boss, just Screech him first and the stuns should stack unless you're unlucky. Also with 3 blasts, cone, pbaoe, stun, sleep and knockback, there's plenty of spaces for different IO sets.
So yep, definitely try Sonic/Kin! No idea about Pain, and hated Cold Dom with a passion so maybe a bit biased.. ;D
Defiant EU
Quaver: Kinetics/Sonic Defender
Semiquaver: Sonic/Kinetics Corruptor
I've played a Rad/Kin corruptor to 50 and found it wanting as well. The /Kin part was good, but the Rad/ part is easily the weakest attack set I've ever played.
I'm playing a Cold/Cold defender (to 38 so far) and the Cold/ set just doesn't cut it. The defense buffs for team members are a hassle to dish out, and the tier 8 and 9 powers take too long to recharge compared to their benefit. The single target debuffs are similarly underwhelming. Sleet is good (but you already know that from /Storm). In all, I'd say /Cold is a poor imitation of /Storm (it doesn't even have a real heal), and you'd find it disappointing.
I've got a Kinetics/Sonic defender that does really well. Once you've buffed it's almost like playing a blaster who can heal and lock down mobs almost as well as a controller. Siphon Power is a must early on, and gives a 25 to 50% damage buff when it stacks. SP also doubles as a great mitigation attack (-25% to -50% damage on the target's attacks).
Once you have Siren's Song soloing is a breeze. Once you have that and Fulcrum Shift you can solo large groups (bosses can still be a problem), but with FS and SS on them they're doing half damage or less.
Since a lot of people don't want to be Speed Boosted (foolish of them in most cases), the single target buffs in /Kinetics get used less than they would in /Pain or /Cold. So if you don't like babysitting the rest of your team, /Kinetics is the way to go. Let everyone know which Brute will be the focus of Transfusion and you're set.
/Kinetic's Transfusion heals for almost double /Pain's Nullify Pain, though it can miss. But it's a hassle trying to heal anyone who's not around the focus of Transfusion. So if you're serious about healing and buffing team mates, having a single target heal like Soothe is much more convenient, and you might go for /Pain.
You should get Mids' character designer if you're serious about getting every last percent out of IO set bonuses. There are nice features that let you find which sets have which bonuses.
Hello, everyone. I've decided to make another corruptor. I'm fairly decided on Sonic/ as a primary, but still contemplating my secondary powerset.
). Sleet and Heat Loss both come with some hefty -res numbers, which could add to the -res from Sonic. (The -res cap is 300%, right?). Benumb would bring the -regen that would qualify it for AV soloing. The -recharge and slows should also benefit my survivability. Also, is Heat Loss effective enough to replace Stamina?
What I'm going for here is the most survivable and aggressive combo I can go with. I know my choices for secondary seem a bit unorthodox - /Pain, /Cold, and /Kin - but I'm fairly sure I can get one of these secondaries to work. I've played /Rad /Dark and /Storm extensively, so I'd really like to keep it between the above choices.
So here's my thoughts so far. I'm not familiar with the IO's set bonuses (Just coming back from a rather lengthy break - about i9 or so), so any help on that front could be useful. For instance, I've heard its possible to cap Ranged defense? Lastly, I've also not taken account the Patron Power Pools, although I would consider Soul Mastery for Soul Drain and Dark Embrace.
Sonic/Pain - With the -res from sonic, along with Anguish Cry, coupled with the +damage from World of Pain, it seems like I could get some fairly impressive numbers. My survivability would hinge on the effectiveness of World of Pain, along with Nullify Pain and Soothing Aura. I haven't run any numbers, so my theory is purely speculation.
Sonic/Cold - This one seems like the AV soloing build if I were ever interested in that (always a possibility
Sonic/Kin - Well, we have Siren's Song coupled with Fulcrum Shift, leading to a fairly harmless approach at capping my damage. The -res from Sonic would only add more damage, which is always good. The reliance on Transference could help me skip the Fitness pool, maybe leading to the Fighting pool (Tough?). That, combined with my Patron Power Shield seems like it could make me pretty tough. I'd also have Transfusion to lean on.
So, here's what I'm asking. I'm quite intrigued on the relevance of set bonuses, and the possibility of filling in weaknesses in each combination. Assuming my character was level 50, which combo would be my best bet taking in consideration each pair's ability to fill in it's weaknesses? I'd be split between soloing and teaming, mostly. PvP is not really a concern here. I'd prefer if I could take down Elite Bosses, but am quite OK with teaming for an AV. Thanks for any help!