yintandiddleipo, Great calendar!
In an ideal world I would like a single "at least two seats" rule, with the second seat allowed to be a token comedy passenger seat. I realise that this is a bit unrealistic.
I'm not to sure about the 50 car limit. I think this is too high. I would like to see cars like the Toyota GT-One. Some manufactures have trouble getting 50 cars for GTS and these are not the sort of cars I would like to see competing for overall honours. You cite the McLaren F1 as an example of a car that can fulfil this, but I think this is the exception.
Also I wouldn't like the laptimes to decrease too much.
I've not been very specific, but in the next set of ACO rules I would like to see more power and (slightly) less grip. However, I don't think this is going to happen!
And finally I would like to see some Jags out there!