Good stuff Jim, well, except for the Avanti.
I really liked the idea of a 914 after a right seat trip in a local 914/6. Boy way I wrong. Sure, I might have found average at best examples but no power and what gear am I in is not my idea of fun. Different strokes but I found keeping out with traffic a chore in the 914. Once going it wasnt bad until I had to shift, then it was bump, grind, guess, oops... every time in more than 1 car.
I wouldnt touch a M96 car, we all have to decide if the risk is worth the reward. As mentioned there are still a few Brit cars that when in good shape can be nice to own/drive. Some of pretty low on power so similar issues to my gripe about the 914 but that might not be important.
Good luck, I wish I had the $$ and room for something like this.