Don't believe people who say /DA is no good.
Hate to spill the beans...
but my Kat/DA kicks butt! Only mid-30s but already he rules in PvP and PvE - just won another Arena.
In PvP only the odd Stalker can kill me. I can go toe to toe with any Brute and out last them.
With DA on auto and stacking, my defence against melee is awesome and if a hit does get through I resist at least 40% of the damage! I resist ALL states and just shrug off troller and defender powers. With CoD up immobile hardly hits me and if some do I just turn on CJ and stack my immobile defence. With Acro I can't be Knocked either.
My only fear on the battle field is probably caltrops and slows but no one hardly has them and usually I can jump away.
My ranged def is low sure but since states don't work on me I just chase the blaster and they always run away, blasters can't attack and run - ha like to see a blaster go toe to toe with me.
Stalkers can be a problem but less than half of them can take my hit points down to death with their [censored] strikes, usually I can heal quickly enough with DR to survive the [censored] Strikes and then it's on!
And with CoD up I see them half the time when they think they are invisible ha that is fun.
I plan on getting tactics later too.
The only thing that ever kills me, in PvP, apart from the odd [censored] Strike is when I get gang banged by two or more peeps at once. But who can survive that? And usually I take one down before I run or die.
PvE is just a joke. Until the 30s I was getting exp faster solo than in a group. I can kill +5s. (Not a mob of them but 1 or 2 at a time.) In a good group with buffs and debuffs my Kat/DA cuts through the bad guys like a hot knife to butter.
I don't use CoF or OG because I'd rather just kill the minions than control them. While I attack the boss or Lts, my DS and Kat AOE attacks usually kill the minions standing around me.
One of the secrets to Kat/DA is Divine Avalanche. Put enhancements in the Kat powers (Acc Dam End). With stam 6 slotted and a few end reducers in the end heavy powers and attacks - end is NOT a problem.
Don't let people tell you DA is no good - it is great.
Regen isn't so great as everybody seems to think - still love playing my Spines/Regen but the Kat/DA has been the most fun IMHO.