The single target chain is smooth and very effective on psy/*, when well developed. And, the ST chain matures very early in a psy/* blaster's career, plus it has very good range. Will dom can act as a soft control for an "outlier", as well as slightly boosting DPA when slotted up for damage and recharge. Telekinetic blast is the heavy hitter, which is helpful because the smashing damage diversifies damage types (nice against psy resistant foes). If you want strong AOE, you'll probably not want to play a psy/* blaster, unless you pair it up with a secondary like /mental or /fire.
I have two psy/* blasters now; a psy/dev and a psy/ice. The psy/dev is a stealthy serial trip mine user who throws in psy nado as the trip mine explodes. The psy/ice is a psycho blapper who relies on debuffs (especially -recharge) and status effects to reduce incoming damage.
I'd check a guide for all these questions... but it seems there is no guide for psychic (it's been awhile now) Does one exist that's not posted on the main guide page?
"Fascinating. I'm not bored at all, I swear." -Kikuchiyo
I keep thinking about writing one for the build I've put together for psy/fire. As mentioned, the ST attack is very smooth. I personally love it. As for psinado... I treat it as a controlling power and an agro generator. Yes, I'm purposely trying to grab agro. I off-tank as often as I blast. >.>
It may not be the most powerful or "best" blaster, but it's the one I have the most fun with. Tolarin's my favorite toon at the moment 
--Virtue--
My 50s:
Tigra Swipe (BS/SR/Dark Scrapper)
Galena Storm (Emp/Ele/Ele Defender)
Master Tolarin (Psi/Fire/Force Blaster)
Considering starting up a new Psy/ since you can do amazing things the colors of it. I've done it before on a defender, and there it seems pretty slick, since single target hit hard (TKB and Will dom especially) and it's always fun to watch it cut through s/l resistant enemies like butter.
That said, the powers look pretty different number wise, Will Dom is no longer a powerhouse attack? the other powers seem comparable or lower in damage to other sets... so what's psychic got going for it specifically.
Is the single target attack chain fluid enough to be awesome? I'd be okay with that (if that's its niche) Hitting will Dom then TK so the powers would smash the enemy at the same time was always good fun... but again, will dom low damage or medium damage now?
And how's Psynado, key for looks to me, but is it underwhelming enough for me to wind up cursing the power?
Likely going /mental for -regen/+regen (like to have the feel of contributing to the teams buff debuff vs hard targets) and the added AoE, But I'm open to suggestions.
*Edit*Started off, TK Blast feels very tough
"Fascinating. I'm not bored at all, I swear." -Kikuchiyo