Hmm, that would make things too complicated to code IMO, actually if your level is odd then the first 3 attributes get upgraded (if you have less than 6 points to assign), if the level you get to is even then the second 3 get upgraded, if you can't advance anymore, then the maxed attributes get skipped and others get upgraded then, so in the end if a fighter has maxed up his intelligence attribute, strength and speed will get upgraded, giving the same result you describe in your post. So I don't see much point on adding that kind of options IMO.