Collinite leaves an amazing deep warm gloss, but I don't like to use it since it dries up white in crevices and is a real PIA to get out. I also never got into the ceramic craze, it's a waste of money IMO. They are harder to apply correctly if you're a DIY'r, expensive, prone to water spots and difficult to maintain. People actually buy products as toppers to protect the ceramic from water spots. So now you're protecting the thing you put on your car to protect the paint? That's just silly.
I keep it simple and use Turtle Wax's '
Flex Wax'. Don't let the name fool you, it's not really a wax, it's a sealant and it's amazingly versatile. After applying a base coat all you need to do to maintain it is every now and then just reapply a quick coat and it'll last forever. You can do it on a dry car, but what makes it awesome is you can apply it while the car is wet. You can spray while wet and wipe or spray and rinse to top it off. It's not prone to water spotting like ceramic coatings, its gloss levels are unreal, and it repeals water just as good as a ceramic. Best of all it's relatively inexpensive and the amount you get with each bottle will last you for years.