I can’t help you with a Mac player as I’m a PC guy but Foobar and Fidelizer sound great. Foobar is pretty intimidatingly to get up and running but once set up works great just doesn't look as pretty as some of the other non free options. You also may want to rethink a streaming service at least for the short term if for no other reason that to get easier access to to digital downloads. Qobuz and Amazon HD allow you to purchase directly from the app and Qobuz actually discounts the downloads if you go with the higher tier services. Building your library you might actually save enough to pay for the services and you can then stop if once you’re library is adequate.
Just my opinion but if your internet connection is good enough being able to hear it before you buy it is a pretty valuable service.
Robot I am and Robot I’ll always be.