Indeed, it is my opinion that the most difficult planes to fly have been non swept wing.
The B737 is a pussycat compared to a turboprop known as the MU2.
Probably true. I've never flown a turbo-prop and my experience of twins was many years ago and, yes, it was hard work at times. That's not the issue - basic attitude and power for safe flight is the issue. Recently I asked a young FO what attitude and power he would set if he were to suddenly lose all airspeed indications at cruise level. He did not know. In a FBW Airbus a malfunction such as that would drop the aircraft into Alternate Law and the AP is not available.
AT 40,000 feet there is a drop off in performance...but come on...what terrain is that high that you have to out climb?
Not terrain but Cb avoidance. I refer you to all the AF447 threads. There we had three pilots who did not recognise that their aircraft had stalled at altitude and did not know what to do. There is a gap in airline training and AF447 found it. I think just about any ex-military jet pilot would have flown out of that situation easily but, and here's the point, they have had the hands-on training in manual flight at 40,000ft and would have flown their jets in the corners of its flight envelope many times. They would have recognised the crisis and known what to do. Graduates of modern airline pilot programmes do not have this skill, knowledge and experience on which to draw.