psi is op !
Then why did u change?!
Quoted from "SΛΤΗΩ"
in 5.1 Warden, Scout and Psi get re-mapped if I'm not mistaken.
Source?
Just from hearing and (I think) it was in that promo movie they posted before we even got 5.0 patch. But I can be mistaken.
You had me going right up until you suggested that Astral Breath would annoy warriors in pvp.
You see if you had actually played a psi you would know that any warrior worth their salt has the ruby that allows charge to ignore CC's. Which means astral breath or choke is about as useful as thin air against them in PvP.
My mian is a Mage, but Psi was my 1st reinc. Im playing it like 2y now, and I also have warrior reinc, so I know about this rubies. But there is a error in your reasoning. 1st think what warrior do is to charge on the target. So it has cooldown (ofc. reduced it warrior has the rubies for cd reduction) but simple pulse when he hits me or even ectoplasm and I can cast astral breath. Also, the warrior doesn't have to be the primery target, astral breath is aoe skill. He still can charge on me but till then hes speed is reduced, and in a crowd it takes him a while to target me. Also how stupid one has to be to cast it without any ectoplasm/astral bodie on?! I'm not saying it's a great skill for pvp, but it's definitely annoying one 
This guy knows what he's talking about.
Not sure how it's on the f2p server, but with the amount of rubies available on subscription server, there's not enough rubies to make Choke worthwhile at all in a pyro build. Most effective version is pure pyro + destabilization.
Depends how you make your build, pyro with destabilization excludes choke, pyro with choke exclude destabilization. Both are strong, and Im using the one with choke, but will have to try the one with destabilization.