I love the PCE PSG sound. Ever since I started getting into TG16/PCE games, I noticed one thing; the music always rules in every game, even if it's the crappiest game. When I got into CD games, the same rule still applied. In my strong opinion, the TG16/PCE has the best game music of all time.
I know what you mean by how it sounds like NES, and I can agree. I think it sounds more like a beef-uped NES, which is quite awesome. I was never a fan of the Genesis sound, it's always sound too "scratchy" for me (an excellent example of this is in "El Viento", but that game still ruled.), rather than the smooth TG16/PCE sound. Also I always thought Sega Master System sound was pretty shitty, although it has a atmosphere to it that I kind of like. The FM sound for the SMS, on the other hand, is quite nice.
A few of my favorite TG16/PCE HuCard soundtracks:
Batman - This is just too good, hardware and music wise.
Dungeon Explorer - You have to beat a couple dungeons to really experience how awesome the music is.
King of Casino - Okay people are going to think I am a dork for listing this one, but I thought the soft music in this game was stunning. It's composed for perfect relaxation and made me enjoy the game a lot because of it.
I'd also like to mention that some CD games had excellent PSG music. The best example that comes to mind is Ys IV: The Dawn of Ys which had INCREDIBLE PSG music.