A lot of readers on Webtoons really prefer longer episode over frequent updates. I believe you can avoid the feeling of disorganization by planning out the entire strip on a smaller canvas, split the rough episode strip then polish each slice accordingly.
I made an offline tool that automatically slices vertical webcomic strips to correct sizes appropriate for various webcomic hosts ex. Tapas.io, Webtoons.com, and Smackjeeves.com
If you prefer using an online tool for this, I highly recommend @knicknic 's croppy (looks like someone already linked it)