I'm going to be "that guy" again, and say that I believe in a higher LA.
Sure, you're already paying in RHD - but at +0 LA, you're still getting 9ths (admittedly, in classes that don't rely on Cha as a casting stat in general).
There's feats to circumvent the massive hit to Wis (such as Steadfast Determination): but yes, requires feat investment.
LA is listed as +2 (if sane).
For the un(in?)sane version, I'd maybe go for an LA +1 at my table.
At LA +1 and 3RHD, it would still make a respectable Cha based character. A Sorcerer would still get 8ths (or 9ths with some shenanigans), as would a Dread Necro or Warmage (Versatile Spellcaster). Innate sneak attack also opens up some full casting PrC options.
Small size kind of sucks on melee characters, but could make a respectable Crusader or Paladin of X (I believe there are ways to key Paladin casting off Cha instead of Wis; or you could play a non-casting Paladin variant, which admittedly aren't great). In regards to Paladin casting, I may be mis-remembering the feat in question.
Also potential for Binders, DFAs, Warlocks and Cha-based psionic types.
...as usual, with the caveat that LA is very harshly judged in my game.