I love this idea and was actually working on something similar last year. My goal was building NFTs (only purchasable with SPORTS) that could be paired together like Splinterlands cards with various skills (and purchasable upgrades) that would have benefit based on the position they were played in. For example quick hands wouldn't be good on a striker but would be perfect for a goalie type thing.

The mechanics I had envisioned were slightly different. The games were free to play in the ranked field but players had fatigue. That being said you could buy things like sports drinks that could replenish their fatigue to get back on the field without rest and move up the rankings. The higher your team was ranked then the higher each NFT got paid. The NFTs would then age based on the number of seasons they played in and after time they'd retire and you'd be able to burn that card to get all of the players earnings released as SPORTS back out.

I was all the way finished with the design process and was even, very slowly, coding it myself to bring out. Then I heard about Rabona and kind of dropped the idea altogether since they easily were beating me to market with execution. I didn't think it would work well having two similar soccer games on chain. I've debated having another game idea that used similar mechanics but would probably move away from football if I tried moving in that direction. Now that we have the proposal system I really hope someone with far more skills than I have can help bring these ideas to life!