Hello Thomas, and welcome to TM. I bought a second-hand Plus 4, 4-seater, five years ago and have never regretted it. The car had done 11400km (now 34800km) and was a very acceptable price. 2.0l Duratec.
To me four seats is a real advantage. Occasionally I have people sitting in the back (ever mindful of maximum loading!) but the big plus is that the rear seats easily accommodate overnight bags, and there is no faffing about with luggage racks and straps.
My height is 1.7m and shoe size 39. I say this because my previous car was a Caterham which fitted my driving position precisely, Steering wheel almost at arm's length with the closely adjacent pedals presenting no problem as long as I wore driving shoes. The Morgan took a little getting used to after that, especially as the steering wheel seemed very close. But now with the seat pushed right back and a small cushion in the lumbar region I find it very comfortable. Some friends (taller and a little older) when getting in the car find it awkward to bend the trailing leg enough to complete the manoeuvre.
I have had heated seats fitted. It is an all-year-round touring car. My wife loves it and enjoys driving it. I hope that helps and encourages your wife to join you (the secret to this is let her drive as much as she wants to and enjoy being a passenger yourself!).