Not NFT-related, but you should check out what zebedee is doing. They're building wallets, APIs, libraries, and services to do lightning micropayments in games. They have a build of CS:GO where you get sats for scoring points in a match and it looks like they're trying to make it easy to integrate into other games/game engines. I'd say go make a game that's actually fun to play (as opposed to a game that serves only as a post-hoc rationalization for the existence of a set of NFTs) and then incorporate lightning micropayments to drive engagement and monetization.