There have been quite a few discussions on this idea on the forums, if you do a search.
If I had to do it over again, we'd be taking more breaks, and shift into a semi-ER earlier.
As far as your plan, you should be able to FIRE in 15 years, and you say you'll work 8-9, then want a break every 5. It seems reasonable to take a break after about a decade, when you're 2/3 of the way to FIRE. At that point you can reevaluate options (semi-ER, new field, back to the same, etc.) Downshifting to part time work at that point to let the FIRE stache grow untouched until it hits full FIRE without any more contributions is a pretty sweet deal, IMO.
More money gives you more options. Hopefully you're in a field/job you enjoy, so the decade will be of work you enjoy, rather than loathe.
Either way, you can get the bulk of your ER savings done here in your 30s, and look at next steps when you're ready to cross that bridge. I probably wouldn't be planning for a sabbatical 5-10 years out, as it will make work seem like a slog in the meantime, personally.
Good luck!