We've had both and prefer the Navigator veranda as well. Some people don't like it because it has a solid bottom and they can't see out while sitting down. I've found that while that is true for looking down at the water close to the ship you can certainly see further out.
The other difference is that while the regular verandas have two chairs and a table the navigator's have one wood chair with a padded seat, a small wood table and a padded bench along one wall. This is a great place to stretch out with a book.
The navigators only sleep 3 which is a problem for some as well. Some of the benefits: real close to the buffet (real easy to go up and grab some food and come back and eat it on the veranda), also you get to do the mandatory drill in Animator's Palette sitting down instead up standing up on deck in the sun!