The position of the wings is important for not obstructing the view to the ground. On the Avanti the wing is mid mounted so if you look out the side and to the rear all you can see is the wing. An airborne commander needs to be able to orientate themselves to the ground and keep as much of a view of things below as possible. Certainly the view from a wide window on the side of an Avanti would be much better forward and aft as a SKA or PC-12.I was under the impression that the Avanti was low noise and all of the cabin windows are between the mid mounted wing and the canards. I do like the Learfan now you mention it, I hadn't thought of that option. An alternative layout is that used on the Fantrainer.
How would an evolved small bizjet go?
As to noise the aft engines would make the cabin much quieter than a SKA but the propellers would generate extra noise like a SKA outside as their turbulence hits the tail compared to a tail or nose mounted propeller. We want to make it quiet so the bad guys on the ground can’t hear it from as far away. Also the wing pusher mount creates a square wave noise as turbulent air and exhaust gas enters the propeller. The square wave makes a pattern in the noise of a frequency that we can identify rather than normal propeller noise of equal or stronger loudness.