Ikagura
Mini-Boss
I feel that it was barely that different unless you check late gen (aka 2000-2001) games that are exclusive to the hardware and could be impressive for something that uses the base of a hardware from 1989.
More than twice as powerful, and yet the best Gameboy Colour games, were almost all games that could run on the original Gameboy. Such as Link's Awakening, Pokemon Gold and Silver (of course Crystal was Colour exclusive though), and so on and so forth.Specs tell that GBC has same cpu (Sharp Z80 compatible) but clocked twice than GB (8 vs 4 Mhz). Also, 32 Kb of RAM and 16 Kb of VRAM vs 8 RAM and 8 VRAM of the original Gameboy.