Fair enough, but did we really need the F-35? The F-22 is a much better performing plane. Yes, we needed to replace the Harrier platform for the Marines, but is this really the best we could do at that?
I'm certainly not sure, but I suspect if the mission had been concentrated around a USMC design team, they would not have come up with the F-35 out of that power plant. Will a Marine in a CAS roll have the needs of the compromises that speed and stealth cost in loiter and weapons load carrying ability. A VTOL/STOVL Hog with a variable geometry folding wing is what the Marines need. They aren't sneaking in hot and fast to bomb distant inland targets, that's the Navy's and USAF's job. Marines basically fly in support of Marines on the ground, and doing so provide a formidable force.
I'm guessing that the AT-29 is the Air Tractor 802 based platform? Yeah, I'd give that to the enemy. The 802 is not pilot friendly airplane, it's taken several friends, one who happened to be Leland Snow's son-in-law that I went through Ag training with at Harold Miller's. Air Tractors in general require a lot of flying to make them work, you're rolling flaps in and out in every turn working a field. You have to pay very close attention to your state of energy or that plane will bite you in the ass and kill you. It might work in something akin to the old dive bombing rolls, but I would not want to have to fight with it.