Pipers/Strutural Engineering/Doors

The only single-engine piston aircraft that I can think of that Piper
has put a door on each side of the fuselage is the Tomahawk.
Except for the addition of a couple wing ribs for wing walk area and a
door frame, are there any structural reasons why a pilot side door
could not be added? Now that Piper has gone to the overhead panel, the
left sidewall is clear of any "controls". (Is the fuel selector still
there? It could be relocated to the center console as it is on the
Saratoga.)