It's a massive difference for you since you're coming from the Note 3, so I'd expect it to absolutely tiny for you, but I think it's the perfect size for a phone. On the other hand, if you're not afraid of rooting you can download Xposed to change the size of the on-screen buttons and make them smaller (I usually do this). By reducing the size by about 25% it increases screen real estate by a significant amount while also making it easy to still hit the buttons.
On an unrelated note, it looks like I'm returning the G2 as it STILL has the same problem as the first one I had, which is honestly just ridiculous. It's annoying, too, because it's such a damn good phone marred by such a small, yet crucial issue. Honestly am surprised more people don't complain about this. I've only seen one reviewer complain about it. I will be returning my trusty Moto X.