Economical in which way? Definitely not when it comes to fuel or maintenance costs.

The problem with super powerful propellers is supersonic blade tips. Curved blades on current projects to mitigate the problem are extreme noise makers. The MV-22 has a tremendous thrust to weight ratio, yet still only pushes 350 knots due to the physics of its propellers. What offers tremendous TWR at hover speed doesn’t have the pitch for high speed performance. If MV-22 was fitted with blades for transonic speeds then it couldn’t hover at low speed.

And when it was flown out of reach of the escorts the MiG-25 was able to reek havoc over much more modern rivalries. Nobody cares if it wasn’t a one stop shop. It had unique capabilities that made it inherently dangerous to cross paths with it.

Who’s talking about the sixties and seventies? This is 2014.

Large SAM bodies don’t appear to suffer the same shortfall of a heavy AAM body. It must be different magic pixie dust on the SAM body. The MiG-31 is pretty adept at striking down minute subsonic and supersonic cruise missiles alike. Even if the fighter is aware of the targeting radar lock the missile itself is passive and gives no warning at terminal dive. Rather the fighter has to maneuver to break the radar lock, which sets it up for the R-40T. (That’s R-40TD for the nitpick ears.) The fighter is at a real disadvantage when the MiG-31 uses its strengths. Oh yeah, the MiG-31 operates in groups, too, so it can be illuminated by a non-shooter. We know the semi-active missiles are not as operationally effective as active missiles, or even missiles with active terminal dives, but they are not exactly obsolete.

Radars of that era in the Soviet Union tended to be crude and myopic. It wouldn’t have been anything better than a range finder for the ground attack role.

Uh, most of the features you listed are either 1.) pointless 2.) incompatible 3.) would need a total rework of the bird. It would not be a Su-34 anymore.

I prefer my foe to fly highly observable shapes with minimal pilot SA. I would hate for them to make an Su-34 style offshoot of the T-50 program.

PAF should be asking for the US to donate them some A-10’s. I know, they aren’t sexy to young ones like the drones.