You are tackling a few things that I have thought of when brain storming a project for a game as far as allowing non-steem users to partake in it but for transactions needing to join the steem ecosystem.
I may have to reread but do you think that you will have them link their existing non-steem account with thier steem account once gained
RE: Thicket Update: Steem "Connections", Dashboard and Games interface layout work. Also a bit on monetization.