Need some help on Psi/Regen Sentinel. Need help with power choices

[Heatstroke]

having played neither and was looking for something different. It seems to me that the Psi Primary and Epic play together quite well. But there are a lot of choices... 

 

What is core in Psi? What are the Must have powers? What is skippable? In the Epic it seems that Dominate and Shockwave are the most haves powers.. Do most people go with Mind Probe over Mass Hypnosis. I see Hypnosis being useful to put a mob to sleep and then run in and hit the two PB AoE Powers.. but on teams Sleep powers dont seem to have as much use.. 

 

The other two AoE Powers are Psu Scream and Tornado. I would think its one or the other.. 

 

Regen I know little about. Havent played in in ages..  I know I need to take the toggles.. but there doesnt seem to be a " dull pain " power. Second Wind looks like Dull Pain.. except its not.. Why have Resilence.. seems like a waste.. 

 

Any Advice would be appreciated.. thank you in advance

[ZeroSaint]

I've played one up through 24 using a build dropped in a thread around here somewhere (I can't get Mids to export on my Mac, but the .mdb is attached.   So far, with generic IO's slotted at 24, it hits like a monster truck -  great on End and no deaths running +2. (I'm actually going to bump up as it's getting a little boring).

 

So-  so far so good.  I picked up P2W grenades to make up for the lack of AOE/Cone  until 18.

Sentinel (Psychic Blast - Regeneration).mbd