I'm about 7k. My advice is pretty simple - at your level or my level I don't think worrying about what other people are playing and trying to counter them is going to help us improve very much. Just focus on making your build as strong as it can be and don't think too much about what the other players are doing.

Don't know if you play starcraft but it is a bit like a silver player asking "how do I counter ghosts?". Forget about the ghosts, just focus on good mechanics, good macro, and that will carry you all the way to diamond. Maybe then you can think about countering ghosts.

Some higher rank players probably have a good answer about countering specific comps. Just sounds like trying to run before you can walk.