You called it a kid's game. That irked me.
Anyway, a lot of these suggestions have been brought up before, and some of them are pretty vague or insanely over-simplified, but with that said, there are still a number of them I agree with, but also a few that I very much disagree with. Although it's too big of a list for me to go over each suggestion one-by-one.
One thing though, I believe there's actually a reason they haven't done custom arrows (something to do with increased lag and/or gameplay problems resulting from them).