One thing I noticed when letting my characters choose IK humans, was that most (all that I recall) racial ability score bonuses canceled each other out. On a point buy/exchange like True20, that means that the bonuses don't mean a thing.
+2 Str -2 Int just means that players can swap 2 Str for 2 Int if they chose.
Effectively I called that it just effected the starting min/maxes. ie +2 Str means that your Str has to be between -1 and 5 (rather than -3 and 3). -2 Int would mean that your Int needs to fall between -3 (the lowest) and 1 to begin.
Really that has no effect after the game begins as you can increase your ability scores.
It looks like you handled things a little different... I'm not sure how.
Honestly while I get great ideas from what you've put up, I often find it hard to follow as you only post half ideas (only the changes) and I don't have my book handy at work to see what changed and what didn't.
I understand why you did it, but it's just confusing.