v40 'fix it because it's not live yet' list:
Following known issues have easy solutions that you can/should apply to your own game:
Quarry bush leaves: This industry is a bit squint, you need a fix to make them processable, its floating around the modding forum. (think this is still in _08)
Nail/cartilage: Both lack healing rates and bleed forever, give em a healing_rate:1000
Discipline: The new Disc system is great, but nothing has any natural skill in it and combat is a joke. Natural novice on all my sentients to produce a little less 'rabbit-in-the-headlights' (natural_skill:Discipline:1 for novices, creature_standard.txt contains the sentients). Disc still heavily impacts combat, but its a bit less 3 stooges from both sides. Anecdotal: creatures will train their disc a bit more during worldgen if they didnt start at 0.
Climbing:
A constructed wall is not smooth unless you built it from blocks rather than stones. (has always been the case, just now matters) They will climb your constructeds, the best is natural smoothed walls, then block constructed. Soil and rough constructs they will climb very easily. This makes a huge differance to your surface setups as i'm sure you appreciate.
Climbing 2-z seems much more of a challenge, they also jump moats now, they will jump a single tile happily, go for 2-wide minimums.