Good critique.
yeah I once saw a proposal for a variation on an air tractor that looked really interesting
There are actually quite a few decent designs for crop-duster air support aircraft.
If the design is intended for low-intensity combat under conditions of air supremacy, then we don’t need fighter wanna-be’s. We need low, slow, long loiter times, and LOTS of them. Every company should have its own air support on call.
Wonderful as it is, even the A-10 is overkill for that role. It was designed for high-intensity combat operations with air superiority still being contested.
AT-802U
This looks like a solution in search of a problem. Plenty of prop jobs out there (AT, Toucano, Cessna) for the third world.
If you are going to replace the A-10 with a single engine propeller plane I would dust off the plans for the A-7.