Hi Brian,
There are so many variables that go into choosing a tripod and head - I agree with the other recommendations that you should really try to find samples of the models you are considering, and test them out in person. Bring the gear that you plan to use, and check the rigidity, stability, and usage features with those items mounted. It's hard for other people to give definitive advice. You need to consider the things that you like to shoot, how you set up (eye level? close to ground? in a blind? in water?), what techniques you will be using (panoramas? macro? long tele? wide-angle landscapes?), how much weight you are comfortable carrying, and over what distances, how fussy you are about sharpness in your shots, how big you print, etc. And cost, of course.
Here's one other consideration that has not been mentioned so far in this thread: will you be shooting any video with your D800E? If so, you may want to consider a pan/tilt head, or ideally, a fluid head. The damping in a good fluid head helps you to make smooth camera moves, which is one of the distinguishing features of a professional-looking video. A pan/tilt head can be quite serviceable for landscape stills, but a ball head (even a very good one) will be less than ideal for video. One disadvantage of fluid heads is that they tend to be bulky, and the best of them are a bit heavy. You might eventually want to have more than one type of head. This argues for choosing a modular tripod, one that can be fitted with different types of heads. With Gitzo's series 3, 4, and 5 "Systematic" tripods, you can remove the flat base plate, and attach a "video bowl" adapter which mates with high quality fluid heads.
That's what I did. I have a Gitzo G1348, somewhat similar to their current model GT3541LS. This is a series 3, carbon fiber, 4 section tripod. I don't use a center post, and almost never use the smallest leg sections. Using only the largest three sections, this tripod puts my D800E at eye level. I am 67" (170cm) tall. The smallest leg sections are only needed if I am shooting on a slope, or over a crowd. If I am only shooting stills, I mount an Arca-Swiss B1 ball head, the predecessor to the current Z1 model. This combination is quite solid. If I want to shoot video, I loosen one bolt on the Gitzo, pull out the Arca and the Gitzo's flat base plate, and drop in a Sachtler FSB-4 fluid head on a 75mm Gitzo video bowl adapter. The switch-over takes less than a minute.
For hiking long distances, I use a different combination: a Gitzo GT1542T ("Traveler" series 1, 4 section, carbon fiber), with an Acratech GP-s ball head. This setup is light, small enough to fit inside my backpack, and certainly strong enough to hold a D800E with 24-70 or 14-24. I can't vouch for its suitability with big glass - since I'm not strong enough to haul that stuff up steep mountain trails. The Acratech has a couple of clever features. You can detach the panning swivel from its normal position, under the ball, and reattach it over the ball and under the quick-release clamp. In this configuration, you can level the panning swivel, and it functions as a horizontal panorama head. You can also drop the ball sideways into a yoke, so that its motion is constrained to movement around a horizontal axis. With the panning swivel as your vertical axis of rotation, this lets the Acratech work as a gimbal head. Both of these tricks are not ideal substitutes for dedicated panorama or gimbal heads, but still useful when traveling light. If my explanation is unclear, see the
tutorial videos on their web site.
I'm not a fanboy for Gitzo. I have had no problems with their products, although I gripe about their high prices, especially on accessory parts. Some people claim that the tripods from Really Right Stuff have better build quality. I have RRS plates and clamps, but have not used their tripods or heads.