A crude idea (sorry guys if it's a bit weird. Feeling like complete crap today):
When on the rearm pad, you could choose to keep bombs, rockets and/or DT's. Example: I upped a jug with 2 1k's and the 500lb and the mission is good with the plane not messed up. When I go to the rearm pad, the clipboard pops up and I'd select which ords I want to keep (decide to keep the 500lber, ditch the 1k's) then click "Rearm". This would ONLY work with ords you originally upped with. So if you took a "slick" jug, you would not be able to add ords/DT's to it on the rearm pad. Another Example: I decide to rearm again, only this time I can "add" ords. The only ords I could "add" would be the 1k's since that is what I had originally upped with. On this rearm, I decide to leave the 500lber and up with the 1k's and "Rearm". Bam, I'm on my way. As mentioned before, this will ONLY work if you originally upped with those ords/dt's.
Another thing is; If the ords have been taken out at the field you are rearming at, doesn't it make a little more sense that you can't reload bombs/rockets (or DT's/100% fuel if the fuel's been hit) at said field? Personally I find it weird that I could fully rearm my plane with bombs at a field who's ords been knocked out, while guys upping from that field can't take bombs.