for me, I've been told my pieces sometimes look too long, but I always separate my paragraphs for artistic reasons, where I think it feels or "sounds" best, euphony-wise. I have a very long paragraph in sticky black that I was suggested to breakup, because it might be hard to read, but the idea of the paragraph was to be a lot of ideas all smearing and running together, so I left it as it was.
I'd suggest you separate your paragraphs based on where in your mind, the thoughts end, because, though we want to think of the readers, your best work is ultimately about expressing your heart, and you can't do that if you worry too much about catering to a platform.
(also if it'll grate on you because it looks weird in your eyes, it's probably a sign to stick to your vision.)