I've never critically analyzed Homestuck tbh, despite doing multiple readthroughs. I could see how it would be a distaction from the beta kids, but imo at around the time they were introduced things had sort of lulled for them. I'm not sure how much story there is to tell with 4 main characters who are all friends with each other. The trolls provided much needed tension the story lacked once everyone got in the game. It's quite an interesting take you have, from what I've seen most people think Homestuck only gets good once the trolls are introduced lol.

Though, I do agree with the character oversaturation, suddenly jumping from 4 to 16 characters got busy fast, especially with Hussie trying to speed run the entire troll session and give each character their spotlights. I'm not sure if he made it work.

I'm not sure what you mean by the writing for them being systematic though.