I believe the yellow ones are the ones with the option for them to fail
Haven't done the slave ones either, though I did see the sex scenes, and they were fun, but not had time for a second run yet, I am just too far behind on too many games.
But, the love route is the true one, so I will stick to it, and over all, I am not complaining. I have enjoyed what I have seen so far, and look forward to more.
True, a lot of times the dev will make notes in the description, or the 'genre' spoiler, I see people tell you when some of the things are going to be optional, for example. That said, there are some tags I can never overlook ...kinetic novel!!!!!
At least something like NTR has the possibility of being avoidable or not the bad kind, depending on the PoV, but Kinetic Novel, you can't get around that. ;p
But I agree, I have a few tags I like, that are rarely used in a way I want to see, or they will include other things I don't want to see.