Idk I think the only fights I would really skip are Wheel of Fortune, Lovers part 1, Oingo and Hol Horse, and High Priestess. Everything else was enjoyable for me. Some of the later fights especially are a must watch.
The way I see it, Koichi is suffering from quite a few problems.
1st: look up some Japanese fighting game character statistics. I feel like back in the day they'd just list some measurements that don't really scale well with other people they are around. I can't remember anything specific but seems like those measurements never made sense if you looked at every character side by side. Artists more concerned with what looks good than what makes sense.
2nd: Koichi's sort of an homage character to Dragon Ball. He reminds me a lot of Kid Gohan.
3rd: he is sort of flanderized due to the second problem. He is the short guy, Araki wants you to know that.
4th: brief mentioning of future themes
his short stature serves as a way to display his humble nature. Later on 2 antagonists for no real reason other than thematic, shrink down to Koichi's size.