Glad to see your enjoying your time in-game so far. And what a great list of suggestions.
Tool-tips for the market units to list stats and details - very good idea. Adding this to our list.
As for PvP - we are working hard on balancing things with every patch (granted wizards are OP right now, this will be fixed with-in 24 hours). However as for best PvP suggestion - why not start small? with a small of of 100 strength - just make some new level 5 units - 20 or so - and try them in PvP, you`ll get lots of crowns even if you loose.
As for the no-risk PvP game mode...this is something we could look at. Hm...perhaps. I do see a good idea here. Taken under consideration, but such battles would have to give no rewards, and we can`t just limit this to friends.