While I like the idea of races having bonuses to specific senses (like keen senses granting +2 to sight- and sound-based Perception checks), I don't really see a great place to note the bonuses with the current character sheet. The Misc. Mod. space is pretty darn small to note these bonuses and I am concerned that putting them in the Conditional Modifiers section will just make it likely that I'll forget it over and over (just because it isn't right next to the perception bonus.
I might suggest that there would be a one or two additional "blank" Perception slots in the skills section, so that I might write next to one "touch and taste" and the perception bonus +2 (from keen senses), and next to another "hearing" and the peception bonus +5 (from a specialized feat or class ability).
While this topic may have been more appropriate when discussing the character sheet, I think that if nothing could or would be done to allow this common bonus to be noted, then either the Keen Senses ability instead should be changed (like a race getting a bonus to all perception check instead, or the keen senses ability becoming much less common).
However I do think it assists in the inclusion of smell-, taste-, and touch-based perception checks which I do like. If they were listed as separate skills then there would be only a minority of people to train in them (putting one rank in spot or one rank in taste is a pretty easy choice).
I have experience something like this problem before with the survival synergies. Writing down somewhere that I got +2 for searching for tracks, +2 when in a natural environment was a slight problem, fitting more just got harder and harder.