I'm not really sure you'll get the results you want on your honeymoon with an ultra-wide zoom. To begin with, they're really not ideal people lenses, and I'm assuming you'd want plenty of pictures of yourselves... and most people look actually pretty bad in super wide angles. Also, for the landscapes, you don't need super wide. Often those shots have a tendency to look boring, unless the shooter really makes use of the foreground elements and extended depth of field. They can be dramatic if well composed, but a lot of boring shots are possible, as mentioned. Instead, I'd consider a Nikkor 17-55f/2.8. It actually reduces what you already have zoom-wise, but the image quality is far, far superior... and you get the f/2.8. It's a very nice overall walkaround lens, and your portraits will shine. Leave the 18-105 at home.
If you're going to be doing serious photography (and really think about this...) I think you should really consider a longer lens, like an 80-200f/2.8, or 70-200f/2.8, although one of those will be a handful to carry around. But, the shots of people excel with one of these behemoths. They're fast, have great image quality and the depth of field separation that makes for pleasing candid shots. But... they're big... they're heavy...not really good companions on a honeymoon.
However, I've been there, and my preference is to leave most of the heavy gear at home, and just take a seriously good, small, pocketable point/shoot which can do 720p video and take really good stills. Look at something that can do fairly decent wide-angle shooting, like 25mm equiv. on the wide end with a reasonable zoom (4x or 5x.) Look at some of the Lumix offerings because they do 16x9 wide-screen video and can do stills in 4x3, 3x2 or 16x9 aspect ratios/formats. Something you can wear in a small waist pack or belt holster. You can take it with you anywhere, and get so many more memorable shots of your time together, which is what I think will really be going on. You don't want to spend so much time on 'serious' photography that you wind up divorced on your honeymoon.
Anyway, just some thoughts.... but whatever you do--have a great time!!