MoG is a fantastic power, even the way it is now. Despite limitations as described above, if you have any trouble with PvE as a regen then the problem is with you and your tactics, not the powerset.
As for PvP, the biggest difficulty is the lack of hold resistance. I find I can silence the arrogance of Corruptors and Dominators (yes, especially the self proclaimed uber ice/kin) with MoG. I tear them up while they panic and jump around unable to land anything...never mind their precious holds. Just know your enviroment so you avoid psi-dealing npcs during the fight.
Epistropheus 50 DM/Regen