One of the dev desires for the new genetic information is for dwarves to know when they are being selected against. Specifically, red headed dwarves should get pissed off if the last X dwarves killed have been red-heads.
1: Fun with Math: Obviously there is a non-zero potential for 3-4 redheads to die in a row naturally, especially if you've got only four hair colors and an even distribution. One thing that would make for FUN is to vary dwarven tolerance for this randomness. Basically, Urist McConspiracyTheorist might see the 5% chance that it would happen naturally as
proof of noble(player) intent. It would take some math to figure out the chances, and the threshold should be attached to a personality trait (new or not). This has the player advantage of serving as an early warning system. (Conspiracy Theorist getting unhappy at the number of Redheads dying could protect you if, by chance, your military is mostly Irish. Maybe you need some diversity before your soldiers mutiny)
2: What else should be monitored? Obviously physical charactoristics and mental ones. Anything else that's touched by the genetics system. That solves the 'Eugenics is bad' desire, but that's a lot of code that could be put to broader use. Religion is another good one, both God and Fervency. Group membership, especially if you're killing migrants and the offsite civ gets pissed. Losing too many cripples should also wierd dwarves out... Care would be taken that this didn't apply to any dwarf getting wounded on the way out. Skill levels? The Soapmakers band together to defend themselves from your wrath?
Edit: This is what I'm talking about:
eugenics stuff
Yeah, I'm quite mindful that when I mentioned people can breed dogs now, of course the enterprising player is going to be doing all sorts of whatever who knows. The timeframe is probably a bit grueling to get anything like that started with dwarves though, as you'd need something like a 12 year fortress to even get started, but the only restrictions I think I'm planning to put in place (in a future release) are having creatures notice when they are being selected against -- it's sort of a tricky problem, but if the last ten dwarves to die all had red beards, I think the other red-bearded dwarves might start to notice and either flee or take action against their leaders, and that's certainly easy enough to code, though applying it outside of a controlled environment like the player's fortress is more difficult. I'm vaguely worried about how much untoward player experiments will crap up the forum with flamewars and racism, but I don't think it'll be so much that it can't be handled properly.