I'm a big fan of Pioneers AVH models (without navigation)
the interface looks real smooth, the units function well and are pretty darn reliable.
for instance, I have the 3500bhs (the 2014 model is the AVH-X3600bhs), this has a 6" touch screen with DVD/CD, BT, AM and FM, pandora radio, and has provisions for hooking up SiriusXM. the reason I like this one better than any of the models above it, is because it has a smaller screen which leaves room for buttons on the side and a disc slot and DOES NOT have a moving face which will sooner or later wear out. if you want a bigger screen, there are a couple of models above it with a 7" screen but they have a moving face to reveal the disc slot hidden behind the face.
having BT audio makes using the phone for a sound source AND navigation easy and fairly cheap, but if you want full navigation, I would look at either a pioneer AVIC or a Kenwood DNX model
that would be where I would start...
then if you want more or better sound after that, I would look into getting a 5 channel amp to better drive the speakers and also drive a real subwoofer (doesn't have to be window rattling, but does make a huge difference in how it sounds) and then maybe a couple of pairs of really good speakers to finish it off
