I used shopify before and it works really well. So I can definitely recommend it, especially for the different payment methods, but you do have to consider the costs. In my case I also had to pay 2% of the transaction to spotify for using the largest dutch payment company here and then still had to pay 80 dollars a month.
So it works well if you have a decent stream of revenue each moment. Sometimes I didn’t sell stuff for a month or so and that was getting costly and once you go there, it’s not easy to get back. (setting up a new shop with all the products etc just takes a while)
But in your case i’d say: go for it. 😉 It will definitely save some time. I don’t think the different login credentials are a problem. Your customer base is probably pretty tech orientated and doesn’t care about that.