Question 1: I think there is a slot for a true greencoin. The key is that it has to be fair, it has to add value to the environment. It has to stay far away from scam and it has to be transparent. All eco/greencoins currently are scam imo, but people do care a lot of this topic.
Question 2: Cant answer that. But i would build a Proof-of-Stake coin. At least thats they ether wants to evolve too. And many people have the opinion, there can only be one real proof of work coin.
Question 3:
That is the most interesting aspect in your blogpost. Bringing gamification into mining, sounds fun.
Good luck!
Thanks for the comment. Please watch out for your voting power. It's below 20%. You should maintain that above 75%. You've been voting too much... It won't work out well for you!