Everything tbh. The difference between the (non-remixed) Chapter 1 pages and the Chapter 5 pages for Life of an Aspie are like night and day. Story wise, LoaA is my first time making an original story since like most people here I would assume, I cut my teeth in my youth making fan comics based on existing properties. So far, I feel I've done a bang up job introducing a non standard character like Susan to the webcomic community what with all the praise I've gotten (that I didn't even expect) from people here who can relate to her in some way.
Also, I think the biggest hurdle for new web cartoonists is marketing themselves because with a site like Tapastic or LINE Webtoons, you initially expect to let the site take care of the rest which it technically does so long as you update regularly, but even then, you can only get so far from letting the site do the promoting for you.
I'm in the same boat. I often find ideas I have for LoaA taking on a life of their own so to speak so therefore I never bother with scripts. Plus I find the dialogue frequently changing on the fly anyway.. For example, my latest chapter was much different starting out compared to the final product that my readers saw. The yogini/guidance counselor Yamada and Susan playing The Legend of Zelda: Oracle of Seasons were two things that didn't exist in initial "drafts" for Chapter 5, but their inclusion I feel made the chapter all the better.