Looking To Replace 18-55mm VR Kit Lens

I have a D5100 with the 18-55mm kit lens, and a Nikon 55-300mm VR telephoto lens.  I am looking to replace the kit lens with something better -- or perhaps adding a 3rd lens like a prime lens of some sort.  With the telephoto, I have the range from 55-300mm pretty much covered.  The kit lens is not bad (for the price), but I am looking for something superior (in the $300 price range) that would cover a similar 18-55+mm range, but has a faster lens and gets better bokeh.  I've heard good things about the 18-105 VR  and the 16-85 VR lens -- but I'm wondering if either one is that much better than the kit lens?  Or would it be better to just keep the kit lens and add a prime with a faster lens and probably better bokeh than even the 16-85?  If I go with a prime lens, it looks like the choices are 35mm/f1.8 or 50mm/f1.8 Nikons.  I don't think I can afford the Nikon 85/f1.8 prime, but the Rokinon 85mm/f1.4 is a possibility.  I don't like the idea of carrying around 3 lenses -- if at all avoidable; but I would be willing to consider this option if adding a prime lens would be a significant improvement in shooting flexibility or image quality.

I also do quite a bit of video shooting, so I'm wondering if anyone has an opinion about any of these lenses as best for videography.

There are so many choices - it is a bit confusing.  Can anyone help me sort out the differences in these choices and what I might be gaining or losing with each?