If the FE2 had been made to accept non-AI lenses, I may have opted for the FE2 (the 1/250th is nice).
Non-AI lenses can be used on the FE via stop down metering. Before
mounting the Non-AI lens be sure to flip up the coupling tab located at
2:00 on the camera's lens mount. Press the nearby button and lift it
up. Stopping down the lens is done with the lever on the camera beside
the lens mount. Also, be sure to flip the coupling tab back down before
mounting AI or later lenses. This goes for the Nikon FM too and some
other models but not the FM2 or FE2 which have no flip-up tab.
As far as the FE's top plate or top deck is concerned, I had (according to what I have read) thought that both the top and bottom plates of the FE are metal. Can anyone verify this?
Yes, they are both metal.
Also, when the MD-11 or MD-12 is attached, the "on/off" switch of the drive unit actuates the meter, right? Thus, would this also disable the flush position advance lever lock?
The meter on the FE can be used with the MD both on or off but
turning on the meter is different for each case. With the MD off
the meter is turned on in the usual way as if no MD were attached
(by pulling out the film advance lever). If the MD is turned on the
film advance lever should be pushed in against the body and a light
press on the shutter release will turn on the meter.