If you reset at all, I wouldn’t reset any more than about 5 levels. Don’t make the jump all the way to the lower levels, because you’ve already come so far! You’re doing better than you think! Resetting just a few levels won’t hurt though, imo. It’ll lower a bit of your immediate burden.
I’ve used this script in the past when I’ve been in a hole to focus on bumping up as many of my apprentice items as possible (and trusting the srs that my higher level items will hold out a little longer), but I also wouldn’t use it exclusively. If I sat down for a twenty minute review, I’d use the script for fifteen minutes and turn it back off to randomize everything again for the last five minutes so it wasn’t just a whole review of apprentice item hell. I uninstalled it once I’d cleared all my backlogged guru items.
I’m also on team do-five-lessons-a-day-anyway. Chipping away at lessons will help reinforce things (and when you’re already at 300 apprentice, what’s five more at this point honestly?). It’s a good habit to get back into, and it reinforces kanji. Win win.
頑張ってくださいね