Was thinking about this
possibility, since the Dispel Fix and PSC fix are in-game. So many CL24–25 builds are much more difficult to play, based on the current mobs, as per empirical experience suggests (Forum comments, some actual IG experience). And I can't say myself if the recent adjustment to mobs with Dispel (greater) has changed the situation enough, so that a Caster with less that 30 is NOT going to have a rough go of it.
Maybe that is simply the current desired paradigm: the extreme power of Casting is metered/balanced by the need to be CL 30 or above (aspect of reliability).
And I'll add: it isn't just about getting to CL 30, it is also a bit about the leveling structure, where being a few Caster Levels below Character Levels, can make a build extremely difficult (i.e., not challenging fun, but a negative experience).
So, my thought is: taking Caster Levels as Epic Feats. Is that OP? I would suggest one couldn't get above CL 30 with these Feats, so they DO NOT function like Spell Power feats.
Feedback to this suggestion?
As Karond has noted many times in the past, suggestions are often based on the personal, and true, I have a 24 CL character that I would be so so so happy if they could reach CL 25, which I feel is the absolute minimum—25% dispel chance—to even be worth playing on BGTSCC. So, for me, I would sacrifice an Epic Feat to gain CL 25, for this build. Thought it would be worth mentioning my motivation for the suggestion (cause I know many Players have CL 24 build ideas, but I always tell them to erase that build, since it would suck eggs on BGTSCC.

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