Forgptten Realms Races, that give +CHA(likely I missed some):
(Lesser) Aasimar
(Lesser) Drow
Star Elf
Can you buy off the LA?
If so, Aasimar can net you a couple of nasty options for Alter Self/Polymorph(Outsider).
Also Wings for a Feat(IIRC Races of Faerun).
Note, that Humans and Elves can take a regional feat(Otherworldly, PgtF), to also become Outsiders.
If you can't or don't want to (ab)use Polymorph, please tell us, what spells you will use.
Would be pretty pointless to max Save-DC's on a Summoning Sorcerer, or take Augment Summoning with a Blaster