Well, only some of their games are crap. It's like this for other systems too, like the GBA. It has some crap games too, you just have to put them in proportion with the quantity of the games released for it. Do this for consoles too, like the PS2. Just compare how many crap games there are compared to how many games have been released in all. For the GP32, the ratio of good games to bad games is pretty good, especially if you considered GamePark's state when they made the games, it was a lot different than Nintendo when they released the GBA. I think GamePark did a superb job.
Here are some games that I think they did a good job on:
ASR
Dungeon & Guarder (Not too bad, a decent effort)
GP Fight
Hani Party Games
Her Knights
Little Wizard (It's a decent fighter)
Mill
Pinball Dreams
Princess Maker 2
Super Plusha
Wizard Slayer
Counting how many games have been released, that's not bad.