In the end, the only financial aspect worth noting is Morgans will depreciate less than most alternatives.
But at the same time that doesn't mean they retain a value close to new. Which means that any upgrade, even a later version of the same model will cost money.
I fully intended to upgrade my Roadster to a 3.7. I even chatted to Steve Morris (Name Drop) about the new 3.7 at the time he was negotiating the engine deal with Ford. The problem with that turned out to be an extra £30k necessary to do the upgrade. Even using man maths this makes no sense. It made more sense to use that £30k to get a Plus 4. Which is what I did.
In terms of which model to chose today.
1) Test Drive all models on your shortlist. Are you comfortable? Is it "good enough"........At the launch, the S5 Aero failed that test because I'm the wrong height with short legs and the driving position for me was intolerable.
2} If you want "Modern" go CX. If you want "Character" go Trad. The CX is only better than the Trads if that's your preference. If you're a fettler, a CX has much less appeal.
3) Buying new is an amazing experience. You can see your Morgan assembled day by day if you have the time. What is not so easy to manage is things on the margins, such as paint "defects" and leather "defects". I speak from experience.
4) Buying used means that you get to see the whole Morgan before you part with any money. You can test seat comfort, you can examine the leather, you can check the hood fit, and bonnet fit.
There's no answer to any of this. Make a decision, see it through, and live with it!!!