Paint what makes you happy to look at, you spent the money on those models, you took the time painting them, you put the skill into the finished work.
Not everyone might like how they turn out, but not everything in 40K is color standard. Some SM chapters are shiny and brand new looking and highly colorful, some are worn and beaten and dusty looking... Some tyranids are painted glow in the dark, others are drab to match their environments!
You are the one who will be looking at and playing with those models more than anyone else, so do what is the most pleasing to your own eyes. If people complain, tell them they can go pay for their own models and paint them the way they want.