Paul, I'd suggest your recent summary is an eloquent synopsis that is worth printing off, keeping in your wallet and referring to whenever you feel the seduction of a polished showroom. I could relate to a lot of what you said and believe I'm far from alone in finding a lot of resonance in those words.
To answer your question further, and as has been illustrated on this thread, many members of TM have had/continue to own other sports cars; one thing most of us share is a love of petrol and vehicles in many guises. Nevertheless, what has brought us to Morgan is as varied and diverse as the colours offered by the company themselves.
Speaking for myself, I love the fact you are not instantly judged by what you drive. I enjoy the universally positive reaction of other road users and pedestrians. Hearing about other petrol station visitors experience with a Morgan makes for an interesting - and longer than necessary! - visit for each fill up. I love the nostalgic feel, in spite of the car being relatively new. The fact that it looks like nothing else on the road always makes driving it feel like an occasion. Lastly, and whilst many clubs will claim this, the TM community is the final piece in an already unique and special ownership experience that makes the entire prospect all the more pleasurable.
NOW, onto the flip side! Personally, I no longer search for automotive nirvana - imho, it does not exist. Morgans do require some fettling. This generally does not include 'stranded by the roadside' frustrations but minor niggles can occur. Secondly, I still worry about where I park and I am still precious about my car; this, as you'll know, is related to your personality and not the vehicle in question. Even when I have bought inexpensive cars, I still take car of them and park them away from all other cars, when given the chance!
There is so much more to say but I will close by saying that I've sold many 'nice' cars and none have lasted as long as the Aero. Part of this would be related to everything I've said above but equally, when you do get the 'itch' (what petrolhead doesn't?) I find myself saying: but what would I replace it with? They really have no direct peer because the package is unique; you can buy faster, prettier, interesting and so on but not all in one package.
That is my 2-pence and written as a stream of conciousness, whilst pondering your question.