How many idea's do you want?
Though I do think one vital thing is missing from all these new game or collectable type projects on the chain.
We need 100 things to have 8 of them be good ones. That's a general rule. Even identical games one game will get more users than the other for some reason.
To make your collectable the one that everyone wants. You need sustainability. A reason why your collectable holds more value, in this environment the value of cards is key I think, Or more so the future value of a card. That there is a decent chance in 5 years the card still holds some value.
While I do not think it is possible is guarantee a price for a card. Especially a less common card. You can establish a minimum price per card for future times. To do so you would need to create a game generator account. (That's probably not the best phrase to use.) A game support account.