I certainly want at least one stripe of Ganzi who has an INT bonus rather than penalty. :P
INT - the ability to think creatively and be open to and good at understanding strange new ideas, is the last mental stat a Chaos-Spawn should have a penalty to. WIS - common sense, dedication, and awareness of the here-and-now, and CHA - friggin' social skills - are far more appropriate candidates.
I agree, for the most part; Wisdom would definitely make a better penalty. I'm less convinced making Charisma a penalty.
... Mostly since my understanding of Charisma (in Sorcerer terms) is that it has the tendency to be hot blooded and impulsive. Similar to force of will, but more accurately force of emotion.
In other words a High Charisma character can fit very well with Proteans if they're passionate.
While we're on the subject, I'd also like to see similar variant options for Androids, with different ability modifiers (including one or two options that get really super ability modifiers in exchange for losing many of their other possible features), different drawbacks, different senses, and alternative robo-powers to Nanite Surge.
Definitely liking where you're going with this.