It'll be an ERC20 token. I understand your feedback around convenience and cost effectiveness, but unfortunately ETH is where everything is. It's where there's the most infrastructure, users, and volume is - I'm sure we could look into a wrapped version if it came to that.
I am actually all for this. Not that it would be any kind of guarantee, but every token i've seen really mooning, have been erc-20 tokens. It might have something to do with the fact that whales trade those.
But since you are visiting in here, i would like to point out that your mobile browsing needs some tuning. Betting multi bets on sports for example seems confusing. Like for example why do i need to click down single bets, before i can access multi bets every time my multi bet doesn't get trough. Multibets and single bets under different "tabs" would be way faster.
Just today i tried betting with a laptop browser and it's whole another experience. Everything works smoothly. But design doesn't translate well to my mobile browser. I get all sorts of weird clitches where my bets disappear. I might be clicking wrong button by accident on touch screen but it's annoying as i need to choose everything again one by one manually.