Not sure about the security sandbox, but given that paddle.com (your payment provider) takes 5% cut you could consider accepting lightning (bitcoin layer2) payments. QR code generation for lightning invoice is instantaneous just as payment, and will cost less than 0.1% fee (payer pays fee anyway). But the security sandbox should be solid, else it will be used for illegal stuff.
Not really. I mean, I guess the lightning stuff makes it settle/confirm faster than doing an on-chain transaction, but bitcoin as a store of value is still essentially gambling. So you'd want to immediately sell it and convert it to USD (or a stable coin, I guess), and presumably you're incurring fees at whatever exchange you're using.
5% for paddle does sound like it kinda sucks, but I feel like any lower fee you'd end up paying with bitcoin would get eaten up by complexity, annoyance, and currency conversion risk.
