I'd like to see WS with some CC prot, either on eclipse or something else. I'd like to see stygian circle changed to something more like drain psyche from psionic assault (dominators) or psionic manip (blasters) cuz as it stands Stygian circle is fun but useless in single target AV fights or the like. The -regen from a drain psyche style power would also be lore accurate! Also obviously fixing Changeling while giving damage equal to it (in terms of Trapdoor and Pylon tests).
Another thing I'd like but is a bit more out there and less plausible is if Mires and Eclipse gave a special buff from AVs or elite bosses. So when you mire'd an AV it gave a special damage buff and eclipse gave a bigger resistance buff. I doubt the game is coded to do this but it would be a nice thing to maintain effectiveness against single target threats.
So yeah, tldr; CC prot and better functionality in single target situations.
Oh, another thing, don't remove forms, but just like bio, make it so we can maintain human form when 'transforming' so we can still stance dance (fun part of the class) but not take on different forms. Still get the flying and jump buffs from nova/dwarf, but for the people that don't necessarily appreciate those forms or want a 'human only' type of character but still being able to stance dance. Canonically, four tentacles pop out of the kheldian's back they can use to fight with. Not asking for something crazy like that as I'm sure animating something like that would be a pain, but just being able to transform without actually taking on the forms would be great.