The 4 gives you only 1 thing over the 3 - a faster processor. I'm still on a 2 and happy. Unless you're looking for raw speed, Visual Core started with the 2. (It still can't take pictures in total darkness, but it's close.)
Pixels, except for Verizon-branded ones - are all unlocked, so just get a plain unlocked Pixel (I'd wait until the 4 was released, to see if the price of the 3 dropped even further), and you should be happy. (The plain one works just fine on Verizon, and leaves the bootloader unlockable, if you should ever need to unlock it [which is one of the first things I did after setting mine up - at the very least, to be able to boot TWRP to do real backups].)
(Just stay away from the "a" series - 3a or, if they come out with it, the 4a - that's a mid-level phone. the 3 and 4 are flagships.