Sorry, I've only read up to page 9 so I don't know if it's been said yet, but here's a random idea that you can chew on...
Concerning the instant vertical thrust:
I rememeber what frustrated me the most in Tribes 2 when I first started. It was the slow vertical thrust when I was trying to reach a door above me from a still position. As well, it annoyed me when I needed to move around inside a base, they were constructly oddly, and until you had a hang of the controls, it was very, VERY frustrating to move around and fight inside them. A lot of this had to do with the level design, but it was the slow thrust as well. It is important to note, however, that when I was moving around outside, it didn't annoy me. It was only when I needed a big vertical thrust to get inside a door in the base high above me. Especially when I missed, making me have to wait 8-10 seconds for the jet pack to recharge so I can try again.
I think the issue in T:V can be rectified in a number of ways. First, lessen the vertical thrust so you don't get instant height. Make it weak enough to appease the vets but still strong enough that it's not like Tribes 2. Then, to help those who get annoyed with platforms you can make the grappling hook available to everyone at all times (doesn't count as a weapon). Make it the "~" key, or somethign that can be easily selected at all times and easy to remember. As well, make a point in the single player to stress how you can use it to aid your completely vertical thrusts for when you need to reach a door in a base, etc. This way, when someone wants to get into a base from a still position, they shoot the hook up, reel it in and use their jets together. This allows them to speed up their vertical movement for certain situation when it would annoy them the most.
Now with this idea, comes many important factors. First and most importantly, the level design. I noticed that in the Arena map, it will have many places in general where it could be very annoying to play if you were using the Tribes 2 vertical thrust. It wouldn't flow well at all. But on other levels, by making more ramps (that lead to a door above you), people won't have to worry about needing to thrust vertically from a still position as often. Also, you'd need ot make sure that there is always something to latch onto above each door. As well, you need to think about how fast the hook reels you in, so it would be benefit those who need it for vertical movement, but wouldn't make it too difficult to hit someone who uses it when they're skiing. (You wouldn't want them to reel themselves in instantly to avoid everything thats being shot at them)
I hope this helps somewhat. I know it kinda goes against the KISS idea, but really, everyone loves grappling hooks and I don't think it'd be a bad idea to make that a *core* part of the gameplay. Yes, it's "one more thing" to get used to but it's a grappling hook, but it's simple to use and looks extremely fun. I don't think people would get impatient with it.
On a side note, I have to say, the video is spectacular. Other than the necessary tuning up and polishing, and the generally ugly trail lines (they're pretty jagged and too long) I think this game will be one of the best of the year. It's very pretty and looks like a lot of fun. I don't see what all the fuss is about. Good job IG
edit:
Read this:
"also, in our current build (not e3 unfortunately) if you kill somebody while they are thrusting, their jetpack stays on and the ragdoll gets thrusted around like a balloon then breakdances on the ground."
I love it! You have to keep that! It adds variety and will make killing people more satisfying. Please don't get rid of it