Here's something else to consider. You could be smart about it and utilize mil leave in order to drop trips at your airline in order to spend that time making more money in the Guard/Reserve, which even as an O-3 you'd be likely to achieve versus your current civilian new-hire payscale. You'd still spend your hard days off at home. In addition, it provides you with turbine currency in the event of a layoff and an automatic potential for secondary income in such an event. The Reserve retirement is also probably better than what your airline offers, so foregoing the ability of getting your 20 year letter and a reserve retirement at 60yo, which when accounting for your 6-9years of AD service makes it an ok little pension, is very shortsighted imo.

That said, I completely understand the QOL bit. Only you can figure out what's best for your family. As a career Reservist currently in a non-deployable billet I can certainly echo those same sentiment for my family and infant son. Of course where I work I don't want to raise my little family, which puts a self-imposed expiration date on the job. No free lunch in life. But on an apples to apples comparison, these are contentions our more senior airline guys can afford to put their foot down on, as their absence at the airline to chase mil days is usually a paycut and more importantly, they have a 20 year letter in hand to cash in any second the going gets stupid at the unit. For you as a young guy that'd certainly not the case for many years. All in all, for me, there'd be no way I'd ever pursue airline employment without either a retirement check in hand, or active membership in AFRC/ANG. No freggin' way. You've chosen to do the opposite and I salute you, you got bigger stones than I do on that account.

Lastly, bear in mind that after a certain amount of years away from service ( I like to say 3 years but don't quote me on it), you're gonna get put through initial medical qualification again as if you were a new guy, and that's something most late 30-some-yos simply don't wish to deal with, (just like people who wait too long to go to college or who stop and then can't overcome the inertia of getting back on etc etc, older people don't like to be put through "young people haze", fact of life) which leads to giving up on the pursuit altogether and losing all those years of service, lest you set your heart on civil service and buy back your AD years that way, but that would require leaving/furlough your airline.

So consider how long you wish to stay away from the Reserves. Don't loiter too long, you might end up pricing yourself out of it altogether. Good luck to ya and to all those lurkers on here thinking about these transition issues.