Hi 98,
Just as a comment, I would like to say that in our Phenix tractor gyro you don´t have any of the described issues. Engine in front provides an extreme cool airflow right on the moment you start it up!. We also have 4 adjustable air inlets, one on each door window and two on top of the cabin. We normally use the tops ones (facing rearwards)to allow air exit the cabin compartment in flight. But on the ground you can put them looking directly onto your face and that´s a relief in hot conditions.
It is summer season here right now (Spain) and we are currently flying in an average 35 degree centigrade all the time. No problem on the ground and obviously none in flight.
We also use specially treated windshields for hot weather countries and it definetely works.
Regarding vapour lock and cooling, engine in front does that job for free. We use a Rotax 914 and it is advisable to keep the engine at idle about 5 minutes before you stop it to allow the turbo unit to cool down properly. This will make your engine live longer. So you can also use those 5 minutes to bring engine cowling temperatures down to optimal at no cost and without using any extra electrical equipment. On the other hand if you want to restart the engine on a hot day within the next 15 minutes after stopping it, prop in front will keep your engine cowling temperature within reasonable limits. It may not want to restart that nicely but you can use this trick: before stopping the engine, disconnect the fuel pump and wait until the engine starts to rattle, then stop it. Restart the engine without fuel pump and connect it on inmediately when it fires up. It will work everytime. This is not in any Rotax manual, I just discovered it by trying different ways of solving that particular problem on these engines. Anyway, vapour lock can also happen on forward mounted engines but one of the reasons will definetely be caused by unproper cowling design.
98, I know this does not help your questions but I just wanted to share with you all, one of the many advantages of a tractor configuration. Good luck on you final choice!