I'm a big fan of the classic newspaper strip, but I think you'll have more success if you adapt to a modern screen-focused layout. That's why I do my comic in a square 2x2 format - it's the modern online equivalent to the newspaper strip. It still reads left-to-right, is has lots of room if I want to do something unusual, and the square format can go on any feed well enough.
Tapas prefers scroll comics, and mobile users seem to prefer that, so if you don't go square, I'd recommend formatting them vertically - it could be limiting, though. It'll help with getting recommendations and staff picks, and so on. Same with Webtoon, as well.
I noticed that the strip Phoebe and her Unicorn moved to a mostly square layout when it went to print as a collection, event though it is a traditional horizontal newspaper strip, so if you want to play with the 4-panel layout any, the square format might be your best bet online. I've noticed that even C&H strips tend to get reformatted to 2x2 layouts when shared on Facebook, reddit, or other social media platforms. 2x2 just does better.
