Hi Big Al
I wouldn't get too hung up on which car you would prefer at this stage. As Steve has said get out to a few dealers and test drive a few. As you are in Surrey then I can thoroughly recommend Brands Hatch Morgans in Borough Green.
Also try to get along to a HopMog noggin in your area and talk to owners and ask their views about their cars. I know there will probably be as many opinions as people sometimes but you should be able to pick up some tips and it will help you crystallise your thoughts.
I come from a history of 4 cylinder Morgans, but graduated to an 8 about 15 years ago, so I feel I can give you something of a comparison.
Firstly if you liked the long legs and effortless cruising of the Stag, then perhaps the +8 would be a good choice. It has bags of torque, you rarely need to change gears, and will cruise effortlessly at quite high speed, the big negative is fuel consumption, a heavy right foot will sink it into the low 20s with ease (fuel injected models tend to be better than carbs) The handling is good but the car is heavier and larger than the four cylinders, so it is not as nimble and "chuckable". You need to be quite brave to drift a +8 on full throttle.
At the other end the 4/4 is lighter, smaller , and much more nimble on its feet , it is highly chuckable. You will need to drop gears to get the best from the engine, and it will be turning over at higher revs to maintain a cruising speed.
In many ways the +4 is a good mixture of the above, although still a 4 cylinder engine, it is more powerful than the 4/4 (depending upon the age of the car and the exact model) yet maintains most of the nimbleness of the 4/4.
As Steve has pointed out , you buy Morgans on condition every time, with luck the right car will find you rather than the other way around, don't get too hung up on extras, there is a vast aftermarket which will enable you to customise the car to your own taste. The most expensive things to change would be body colour and trim , so make sure you chose a combination that you really like, (and there are so many to choose from!) and then work with that.