just my 2 cents to the devs and then some tips for the userbase
Devs:
1.) For people already on crypto like me, is a lot easier to use wallets directly instead of a 3rd party, so add a button for BTC/ETH/etc. payment.
2.) Consider adding other common cryptos like Zcash and Monero(or a derivate like electroneum) since is probably easier that you convert it on your side because BTC is not minable anymore and ETH difficulty make it hard for those without massive GPUs.
Userbase:
1.) for those with problem getting crypto coins due to Banks been an ASS or because your country is not listed on U.S exchanges like CoinBase.com, you can use localbitcoins.com where you can buy and sell crypto with direct transfers to/from your favorite bank(and other methods) and is user to user, hence unblockable.
2.) Note localbitcoins.com is a user to user exchange site, the crypto is protected by using escrows but don't take my word as gospel and google some tutorials and best safety guides for this system, since well nothing online is 100% free of problems.