Coinbase is the same as bitpay. Maybe even worse, as you won't even have the privatekeys of your funds and they are strictly regulated, freeze account funds at will and so on
Most likely you missed something from my post, please check bold part below.
If you don't have enough technical skill then you may use third party API like coinbase (But is not recommended).
I didn't recommend him to use, it's just a option. It's not like worst as you said. Do you think no one using their API services? I am not supporting them to use but not like you describe. Coinabse also freeze my account but their good thing that I like, they return fund. Until you withdrawal your fund they will not freeze your fund there. I know privates keys belongs to them and that's why fund should not hold there even use their API.
However, I have visited OP site likely his business on start up mode. So you may choose any easy mathode for now. Its matter of time , you will learn everything coming days.
Anyway, OP should use BTCPay server since most of people suggesting it.