As for Na'vi River, we rode it three times. Two with day of fast passes, and once in standby after an FoP ride. It's a great attraction on it's own. The level of detail is amazing. It does feel too short, but I did time it at five minutes on the nose. I kind of thought they could slow down the water current to help you take in all the elements, but I'm sure they won't while the lines are so long. The Shaman is really cool, but I found myself enjoying a lot of the other touches more. The queue of this one seems less detailed, but considering the level of detail in every part of the rest of the land, you can forgive them a little slacking here.
The land itself is very cool and extremely well-detailed. You can randomly point your camera anywhere and take a great shot. It's impressive. Lots of touches. The nighttime part was also really cool. It's pretty dim, but not un-navigable.
Every walk through Windtraders we saw Banshees available. We bought two our first day, and they had four colors available (I think there are eight total--not 100% that). Other walk-throughs I noticed at least a couple of additional colors.
Satu'li Canteen instantly became our favorite quick service on property. We had the beef (w/ chimichurri) and the chicken (w/ herb dressing) bowls on our first trip. Kids did the hot dog and burger pods, and later the quesadillas. I liked both the beef and chicken, but slightly favor the chicken with herb, but either one is a great choice. We did the hash on each bowl. It's great. We also did both desserts, and I prefer the blueberry over the chocolate, but both were good. The chips that came with the kids' meals were really good, too, but my kids weren't into them. My son preferred the quesadillas to the pods, and my daughter did the hot dog twice, but said she'd get the quesadilla if or when we return.
Also, the cast members who were busing the tables there do a fantastic job and really stay on top of things. The self-serve drink station is also a much preferred set up. Finding an indoor table was never hard. I'm pretty sure they were policing the tables for those with food on the indoor seats at least.