I'm sorry to bump this, but MusicBee would be a enormous succes on Linux because of it's logical UI and massive amount of functions. A combination that is very missed. Since the Linux community is largely populated by coders, would it be an idea to scout for a talent which can do it for you Steven? You can always look into the code and call it a day in the end. At the very worst it becomes a slow hog of a program which will not carry the name but may inspire others to make a decent media player for the OS group. There could even be a large chance of sponsors since large companies are increasing their investments in Linux. Maybe not something to do this very moment, but I'm drooling by the idea of you sending some emails on a rainy Sunday to a carefully selected coder and/or company.
(Also, it's very easy to make a dual boot with linux and since it runs well on slower hardware an dusted old computer will suffice.)