I'm a huge fan of FM game music, love those PC88/98/X1/etc. games. I've tried to do similar stuff with Mega Drive / YM2612, if you're interested:
https://tomy.bandcamp.com.
That's some heavy hitting stuff! Really like the drums. I'm a bit interested working with OPL2 too, but atm I have no way of recording from hardware, and I'd like to be able to do that.
So now for my recommendations...
Dengeki Nurse 2 (PC98) - First game is not bad either, but I favour the sequels music. Rocking stuff!
Marine Philt (PC98) - From the same composer as the previous, little more atmospheric. The main "suspense/tension" theme is one of the best I've heard of its kind.
Cyber Block Metal Orange (PCx8/X68) - Melodic fireworks from beginning to end, my preferred version is PC88.
Dialide (X1) - Not so known X1 shooter, with awesome and technically impressive music. It's all FM only.
Dios (PC88) - Recently found this, and it's really good.
Ferill (PC88) - I'm sure nobody knows about this. It's a puzzle game, not sure if commercial or doujin. But the soundtrack... very good sounding for being a '89 game.
Super Star Shooter (X68) - Not many tracks, but couple of them are very memorable.
I'll second that internet radio from first page and Cosmic Psycho too, great stuff.
Check out this site also:
http://vgmrips.net/packs/, you can browse music by chips, composers, systems, etc.