So I don't know if the $4k and 1 year of payments left on our minivan means:

1.) I have $4k left on the minivan and it'll take me 1 year to pay it off; or

2.) I have $4k left (on something else) and ,in addition to that, 1 year of payments ($352/month) left on the minivan.

Once you've got the monthly minivan payment paid off, take that $352 and put it in you vacation fund; house remodel fund; kids' activities fund; 529 fund; activities for adults fund, etc. Ditto with the $3.1k childcare fund. When one kid needs less it, move it over to one of the above mentioned funds or another. Ex.: So when the 5-year-old's after-school care costs go down from $1k/month to $500/month, move the $500 to 1-2 fund or more.

As others have stated, I would not give up that flexibility with young kids. Update your resume every six months, so when they're in middle school, you can pursue a job with less flexibility and more money.