I think it's more the color combination rather than the flag you don't like. I detect many with red, yellow/orange, blue, as well as red, yellow/orange, green. Naturally, flags of CAR and Mauritius must be a big thorn in your side. I'm surprised though that you seem to like South Africa so much.
I like your observation. In general, i dont like flags with three stripes, and flags with four stripes are terrible. I also dont like colorful flags very much. I focus on the design of the flag. I like flags with symbols and cool designs. The reason why i like the flag of South Africa is because i think the design is beautiful, and the colors fit in with it. Thanks for sharing your pov.