You'd think that they would give DAK some kind of "Withdraw and Refit" ability to dispose of unwanted 250s if they were going down this deployment system rabbit hole.
Agree with this, as Katitof says the 250 is a staple for me too, but it would still be good to find another use for them later on in the game. I never really feel as if I need more than two of them at a time, and the waste of popcap kind of puts me off calling more in as the game progesses.
I'm sure the deployment system will change over time, it does feel a bit weird that you're only option as far as AT infantry is to call them in on a halftrack.