I have bought my the the unreal bundle and now doing the c++ fundamentals course (that's also my first one), I have a good experience and
I want the Math for Video Games course or maybe the Unreal Engine Multiplayer Master Course.
For you I would say only buying the mobile course, if you can imagine for creating mobile games,
if not then the turn based strategy one, because I think the other course is part of a serie and I would prefer to do the other courses before, even if you get the code of these courses provided