I had planned on that being the case. I wasn't sure how that would affect things in the E6 world... My thinking was that a character with an additional +4 to an ability score is choosing specialization over generalization, which tends to balance itself out. For instance, a sorcerer with a +4 to Cha (especially over the course of the first 6 levels) is going to have a harder time than a sorcerer who only has a +2 to Cha, but a +2 to Con as well. Also, that's something that each DM could keep track of and deal with on a case-by-case basis. Maybe it could be resolved if I just include a note saying as much?