I was thinking fire/psi as my starting combo...
EDIT: or mayhaps a grav/psi. I'm focused on psi secondary, i've heard it has rather neat aoe stuff. Grav i've heard is useful for the utility, porting mobs and intang'ing them, meaning you can build dom in regular safety... sorta.
Still wanna know peoples oppinininions
Solo a lot?
In high lvls it hardly makes much of a difference what sets you pick, more a case of preference, style and skill.
Lower-mid lvls: mind/ and secondly grav/ prolly imo.
As far as secondary goes /ice is great because of -speed/-rech and PB and very nice ST dam.
/nrg although one of the lesser secondaries overall, is pretty good for solo as well due to the the KB and (stacked) stuns which provide nice extra control especially when paired with a pimary that has (AoE) stun. The AoE dam totally sux, then again you get PB in here as well. 
Gotta wanna put up with the slow animations of /nrg though...
The brutal AoE of /psi is only relevant starting lvl 38/39 when you have the hugely overpowered PSW at your disposal.
Just pick a combo you feel like playing. In the end it's possible to solo (or team) any domi pretty easily regardless the powersets.
Domi's are the class for the delicate, daring, smart and subtle souls.
Enjoy! 
Not wrong about the squishiness and aggro magnetism!
Altho I've noticed that pure plant seems a good choice, confusion helps with aggro and the spirit tree has saved my life so many times!
@SkullFester
I'm not changing this signature until I'm proclaimed 'King of the World'.
Grav/Psi is not a good solo choice. You will have a very hard slog to 38 and then you'll just wish for bigger mobs.
Plant is a very good choice for a new dominator. So many great powers. With Creepers and Seeds you can solo most mobs in relative safety.
Thorns isnt a bad secondary to go with plant (especially from a theme point of view) and it is the only set to get Aim.
As for other secondaries its worth considering fire for fiery embrace (and just great damage in general) or energy and ice for powerboost. Domination + powerboost is just great.
Personally I'd say Plant/Ice or Plant/Fire for a new dom player.
Thanks for the advice, although i went with fire/psi in the end for pure mob slaughterage
This probally wont help much cos ive only ever had one dom, but i use a plant/fire.
The plant/ is good because, at level 12 you get a 50ft, 60* cone, confuse which, when soloing, covers the entire mob area easily.
Plus, the fly trap you get at level 32 has roots so it can AoE imobilize if it wants to.
Carrion creepers are good but their better for bigger groups than they are for solo sized groups. Although they do help when in a sticky situation.
the /fire is very useful there are quite a few AoE attacks and there are 3 quick recharging powerful single target attacks, that if used in succession can easily kill an opponent quickly considering the dominator damage output,
Also, currently on my dominator, i am level 39 and my diff is on viscious, its quite easy most of the time, and im pretty sure i could manage on ruthless, with a little bit of trouble, but it would work i guess.
So yer thats my little add on to this topic.
Basically:
Plant/ give an ealy on confuse; /fire gives a high damage output; you can easily solo on viscious once you reach 32
I usually solo on relentless with my domies when I get stamina... Domies are fast soloing, and usually, safer than others ATs.
PS: btw, seeds is the lvl8 power in plants/
I got a Fire/PSI Dom its a struggle to lvl 38 from their any noob and push the 2 or 3 buttons you really need to use.
I've just dinged 38 on my fire/psi
You were right dark shanir, just a few buttons is all it takes!
It was painful leveling up to 32, but imps made soloing a lot easier, and then PSW has just made it pure awesome to play. Im happy with my choice
After dinging my MM to 50 (Yes, yes VEATS are finally coming :P)
I feel the urge for a dominator, but from what I hear they are pretty squishy and can rival tank's taunting ability
So really, i'm looking for a set combination that'll ease me into the dominator mind set, maybe try some others later.
Basically, I want to know the easier combinations, which ones are a challenge to play, and which ones give you downright grief. Oh, and i'm looking to solo with mine a lot.
So please: The power combo's that in your collective oppinions are easiest on you for solo, to the ones that are downright brutish to play.
Domo arigato, mr roboto.