Welcome @AmesFisher
Bitcoin is the king and has the biggest community so far. You may don't know but there are surely companies providing solutions for businesses to help accepting multiple cryptocurrencies. What I mean is nothing is stopping you to accept only 1 cryptocurrency.
To be honest I am not excepting to see bitcoin cash in an online shop. For me, to see Bitcoin and Ethereum are fine, but if I would need to choose I would prefer Bitcoin of course.
Most business owners don't want to accept Bitcoin because of its volatility, but there are solutions for businesses to have their sales automatically converted to fiat (i.e. BitPay) so there is no fear anymore. Let's say I buy a 1 oz Gold Bar Credit Suisse for 0.10 BTC, I pay in Bitcoin but you, you will receive ~$1000
(I am fine with buying sovereigns for £275 to £300 but I will like to see a loyalty reward program lol )
Would anybody on here want to buy physical gold using their profits?
Yes, definitely