I liked his Video Girl Ai manga back in the day (?1997-1998). The characters went through a lot of troubles and the relationships got turned inside out and went through a blender, but I enjoyed reading it..

What comes to mind first when I think of his works are the female characters. He was drawing girls with short skirts back when it wasn't common to do so (mid-1990s). Eventually just about all female school uniforms in anime and manga had short skirts, but he was one of the earlier adopters of it.

I've only seen the DNA^2 anime. Back when I was collecting cels from it I preferred getting Ami cels to Karin cels. Just about everyone sought out Karin cels first. I haven't read or seen any of I's.