for me i think some of the most important things that will keep readers coming back are
- aesthetic of the story - is it pleasing to look at? are the speechbubbles and characters spotted correctly? ik some readers have pet peeves with bad directing so it’s just something to look out for. along with that i would say grammatical/spelling errors are a quick turn off for some so be extra careful and proofread.
- plot - is it interesting? do i want to know how the characters change and how possible problems are solved? is it something i’ve seen millions of times before in other stories? try not to be too cliché and branch out. don’t make too many problems though because then it can be too chaotic.
- characters - are they likable? is there diversity? is the main character someone i want to spend the story playing as? are they surface level people? always make sure to develop your characters and make them relatable. let them have quirks and abnormal likings and special things about them that make them them. give them inside jokes and real relationships that aren’t based solely on looks (: also about diversity make sure you are not falsely representing any groups that you might not be familiar with; take your time to research and maybe reach out to people of that group for help!