ermmmm - you get Aura and 3rd Cossie slot at 30?...
Seriously though, the same thing happened to me and my blaster in CoH - I took a break for a while, tried some different AT's and went back to him later - I realised I'd missed playing as him, and all was good again 
Also at 32 you get one of the coolest moves in the game, Eagle's Claw. You starting to get close to St Martial too, which I think is not only one of the best zones in CoX, but also has brilliantly written missions.
The Smoking Demon
Ash/Tar Corruptor
Union
@The Smoking Demon
once 30 you are a nice level to PvP in sirens 
and at 32 you get new SO's :P
Eagles Claw doing critical damage with build up, that is something you have to should look foward to, from regen you can get MoG thats a kinda cool power to have. Not to mention new zones aswell as new and more enjoyable teaming experience.
Like Bloodrush says though, sometimes it's best to take a break from a character, then when you come back to them you enjoy playing them more.
The Smoking Demon
Ash/Tar Corruptor
Union
@The Smoking Demon
do what i did, make a new stalker, lvl him up to 22, get tired of him, log back on your old stalker and experiencing how much more fun he is to play
Martial Arts is just one of the coolest looking sets in the game! Got Cobra Strike? Get it, its much more useful than you might think. Cant comment on Regen as I've never had it, but I will say its bloody hard to beat on a scrapper in Sirens. Show us your build, maybe a respec will help?
I have too a MA/RGN stalker, and i only see 1 weak point, he cannt avoid attacks, that build only can heal self and resist damage, but hey! others builds cannt resist damage and if they hit them are dead
ill post my build for help coz i dont know what powers are useful and how can i do it better
hi all, ive got a MA/regen to lvl 29 and he is borein the hell out of me, but i cnt be botherd to make a new char again, cud ppl plz inspire me to carry on playing him, thx