Agreed about the first part, we cannot sully the perfectness of the Lego minifigure with any impure blood! Death to those who mix and match parts!
That being said, unfortunately, more people convert yellow figs into fleshies than the other way round...
Completely disagree about detailing, I feel like it makes the figures more immersive and interesting to look at than the simpler ones. That being said, I have seen a few instances where I agree that less is more...