In contrast to the above, I have been working part-time for 18 years, in order to spend time with my children. I haven't found any difficulty maintaing skills, getting interesting work, although there are clearly some higher level jobs I could not do part-time. Most of these are a lot more work for not much more money so I don't cry too much over that. Since I am a public servant I accrue entitlements like sick leave, that would not follow me if I worked full-time intermittently. There is an appeal to intermittent work (namely , long breaks!), which I may consider later on.
Since finding the way of the mustache and becoming much more efficient with money, I cut my hours down from 0.7 FTE to 0.5 FTE...because I wanted the improved quality of life now, and I didn't want to fully retire before my kids had got through tertiary education.
As it turns out, I am still building the stache and improving home equity. But I've often advocated doing just what you are suggesting... working enough to cover living expenses and letting the stash compound: as my kids become independent I may do just that.
Fundamentally though I guess I'm a "downshifter" rather than "go at it full on and FIRE" type person (too late for me to RE anyway, it will just be earlier, but not early!).