Without any paragraph breaks - which makes reading posts like that brutal.
I also have an Oppo 103 with my music backed up to a 256 GB flash drive. It works, but you are very limited in how you access the tracks and there is no search. Therefore, it you want to find say the Windham Hill stuff, you have to press the remote a zillion times to locate it.
Your next step should be to use server based software like LMS to house the music. It offers vastly more options for locating content and allows for quickly creating playlists on the fly. All accessible from your smartphone remote. And centralizing the content allows for sharing it across multiple systems as I do. All you really need for playback is a Raspberry PI computer with a digital interface or HAT based DAC for about $120. House the data on any computer/laptop.
Enjoy the world of not having to shuffle disks in and out of jewel cases!