OTOH, if you are not planning to sell any time soon (and I imagine you aren't), why live your life for re-sale? Especially when it's not a big deal to disconnect and re-connect the water system (in the grand scheme of things). And then you would not have to be hauling around useless (to you) fluids that have weight
and free surface area effects (depending on how much fluid you have; likely not an issue, but just saying).
As long as you can be sure there is no liquid in your system (blowing it out or etc.), then you don't need anti-freeze in it, whether or not it is hooked up. Normally one puts in anti-freeze to keep the existing liquid from freezing and damaging things (or any possible residual liquid after things have been drained), but it should be possible to make absolutely sure everything is dry (including inside pumps), and then you have nothing to freeze.
By the way, automotive-type anti-freeze does come in pink now, although I'm sure you have the "RV" stuff. But I'm just saying that the automotive stuff is no longer only green.
"Automotive" = Ethylene Glycol = toxic
"RV" = Propylene Glycol = non-toxic
In climates that do not get too cold, Vodka is often used in boats for winterizing the water systems (not the engine, but "house" systems). It is not as annoying to get rid of as the pink stuff, which can foam and leave a bit of an aftertaste (not permanently, but takes a lot more flushing to get rid of, especially from a water heater). I'm not sure the exact freeze point of Vodka, but I can tell you that it is NOT used in places that get down to -20F, and is used in places that get down to about 10F.