Hi, thanks for the post! Always nice to hear of suggestions
#3 and #4 are definitely in the pipeline for the future, #2 I'm not sure about, I think I'd rather have an in-game tutorial.
#1 Probably won't happen, the art style is what it is and it'd be far too costly to completely change now. That said, it'll be open to mods in the not too distant future if someone wants to replace the default graphics :)