Unfortunately we are limited in my State to I think 35% on the front side windows. Nothing permitted on windshield. I will get the front sides tented soon. The rear side windows are already dark from the factory. Do you think a ceramic tent would help on those windows?
You can get ceramic film that blocks 99% of UV and 80% of Infrared (which is heat). At least, I've seen one (CarbonTek, IIRC) that is that much. There may be other brands that block even more.
The one I looked at has film as light as 95% (i.e. only blocks 5% of visible light, but still blocks 80% of IR). I would think that would be basically unnoticeable on a windshield. If we didn't have state inspection stickers on the windshield here, I would get that.
The Virginia limit for front windows is 50%. I think I'm going to get 50% all the way around (except the windshield) and then maybe a sun shade (a la this thread) for the windshield. Blocking 80% of IR all the way around should make a big difference in how hot it gets inside. And 50% on the back and rear sides should result in a final of about 9-10% of visible light coming through those, which I think will look nice, too.