Some of our group are D&D noobs, so patience may be required at first. That said, we've been doing freeform play-by-posts for many years now, with one that ran for over 5 years and only stopped when the forum itself shut down, so don't worry about any of us flaking out. Incidentally, we'd ideally be looking for a nice epic campaign to take us (eventually) from 1-20, so if you've got some homebrew stories you've been dying to test out, we'd be glad to tackle whatever you come up with. In terms of roleplaying balance, I'd say we mostly prefer a straight-down-the-middle combination of combat, intrigue, and lighthearted downtime.
So I could do this. I have never run this or played D&D 5 yet, but I have run many other game systems over the last 15 years and well experience at learn/run and teach new game systems to people.
Sure, we'll take you up on that offer! Most of us aren't very familiar with 5e as well, so it'll be a learning experience regardless. I'll send you a message with a discord link to discuss further.