The fact that you can put random rap part into your non-rap song doesn't mean that you should. Some songs could be much better without those parts. To be fair some artist pull this off nicely, so it's case by case but I don't like it more often than I like it.
I've seen many people online that only listen to metal, where vocals are all screams and growls and... How? I need at least a few seconds of clean vocals in a song. Let my ears rest for a while.
Nickelback is okay.
I don't mind listening to music in other languages than English. I love Japanese music and I can understand only some of the lyrics. In some cases I even wish I didn't understand them at all.
Country music doesn't really bother me.
I like new BMTH more than the old BMTH.
And a really controversial one: I don't like Vocaloids. Just not my cup of tea.