The problem with talking about taste is that you know there won't be any. Even if you call them "mammaries" in the game, you're still going to see them mostly when they get cut off, mutilated, or are severed from the body of the creature who once possessed them, and potentially when some adventurer gets it in his sick head to start throwing it at people like Oddjob with his hat, decapitating people with the absurd throwing mechanics.
I doubt that Toady fears moral guardians, I mean, this game is already something that really only appeals to the M crowd, anyway. Even if there were acts of sex in this game, the simple fact that you can't see anything would probably prevent most people from getting upset. (Remember that the GTA version of Hot Coffee that was perfectly fine by the censors was the version where all you saw was the house, and heard sexual moaning, and it was made quite explicit that CJ was having sex, but that you simply couldn't see it.)
As for this game hitting FATAL levels of perversion... I hate to break it to you, but we're already a bunch of raw-intestines eating, childfall-creating, Goblin-Fortress making, blood pool for the blood god clamoring, slave-wanting, elf and kitten torturous and genocidal group, here. If rock bottom yet lies below us, it isn't very far. (I think the thing that sets us apart from FATAL at this point is forced abortions by melee combat (I.E. the "FALCON PUNCH" crowd), extremely detailed play-by-play rules for sex/rape, and an obvious hardon for professional wrestling. Heck, you can even roll for anal circumference if you mod anuses into your creatures.)
As for feces, Toady actually recently said in a Q&A that he actually likes feces for the ability to use it as manure, to make you clean up after livestock, and for having to build sewers. The only reason he's holding off is that he doesn't want to force "potty breaks", because he feels dwarves take enough breaks over the course of a year, and he doesn't want a "you gotta go" message to pop up in Adventurer mode during combat, which would "ruin the immersion".