My view on this is based on the belief that there is such a thing as a light car. A 2cv is a light car. There is nothing about a 2cv that is genuinely micro despite it being minimalist in many ways. See also DAF, Fiat 600, Trabant and so on. With microcars tending to be collectable it is the light cars that represent a source of excellent cheap classic fun. Of course there is a blurred edge but in essence a microcar is minimalist to a far greater degree than a lightcar and of course, small. Often too small to be useful in size or engine or both. Tricycles have there own following which splices into Micro/Light cars. To me a Reliant is a light car not a microcar. That does not mean I do not like them or degrade them, it just is. Likewise kit cars splice. There are very few kit cars that are microcars though. Most are light cars with trikes being small in accommodation by choice of wheel-plan rather than by other design constraints. Many micros are trikes because of reduced tax, drag and power source/engineering choices to make lightweight cars. There is a subtle difference.
The only real issue which I wonder about is that Microcar Rallies are tending to field more Light cars and less used Microcars in direct proportion to the alleged value of said microcars. I can only assume, therefore, that a differing type of person is taking ownership of the Microcars even if it is through age, though collections of cars reduce the pool of available cars to go to each event unless the collectors choose to buy small car transporters. It is therefore not surprising that quite a few cars in use at events called microcar rallies are actually light cars/kitcars since they keep up with traffic and are cheaper to buy and maintain in many cases. You can see where this situation can lead in respect of Microcar rallies really being microcar rallies as they used to be. 'Herds of micros sweep majestically across the plane' seems to be slightly less likely these days.
As to if kitcars are to be classic. Yes they are. Look at the 50's specials which are now becoming rare collectables with quite bashed about modified ones being returned to 'traditional' period form. They are not worth a great deal and the scene is very like that of the early Burford days in Micros. Where is their rally, Burford! Attend and find a group of nutters who are really into these things with great knowledge. They have the same outcast attitude from years of ridicule from mainstream classic car types. All rather refreshing in fact. The early kitcars are on the move and certainly classic motor sport varieties are becoming very expensive. It is area of great interest to me as I dabbled in kitcars. Get Filbys purple covered book on kitcars and just about every on in there is a collectable. Perhaps part of the attraction to me is that it is a very hands on hobby, as was microcars, because it is hard and/or expensive to buy in the skills to turn a car into a genuinely usable machine. Especially when it has little residual value. These folk have interesting tales to tell and technical know how. Collectors can be interesting but can also be totally none grubby folk with no technical skills. I begin to drift from being able to be fully connected to their interest as I am primarily a fiddler over a collector or driver.