I remember reading about the widgets, apparently they are quite popular with those that offer multiple options to customer. Add to that the peace of mind to customers that there will be no KYC issues, it makes a viable solution for those that some technical knowledge to install it.
If you are colocating your server, do you have any reservations about engineers accessing the server? Or if you have purchased your hosting, do you have any concerns about hosting it on a third-party server?
Yeah I didn't want to do KYC to use some other payment processor for BitMixList.
BTCPay Server works just fine for this, for alts I have the Trocador widget to let people automatically convert them to BTC and they can also pay direct XMR with the Monero plugin.