Here is the key to your problem. It is hidden in these words.
You see, despite all the braggadocio, veterans actually spend the vast majority of their combat time in these low speed scenarios. Skiing isn't really a combat state, but is more a mobility effect used to enter or escape combat at high speed. The amount of combat that actually takes place in mid-motion is relegated mostly to flag-play.
Effectively, any movement you make easier for the newbies, you make incredibly easy for the veterans to abuse beyond all belief.
This "tighter feel" in the air is an example of what I'm talking about. When a veteran sees this, they don't see a tool to help the newbies. They see a tool that's going to overempower the veterans to the point of making many of the historic weapons much less useful. They see a sudden decline in the player's capability to fail at doing something. In other words, Tribes skill exists across the entire spectrum, from basic movement to high speed movement, and in fact, most of that skill rests in the low end combat. To simplify this low end combat simplifies the vast majority of combat to be found in the game.
Example: a player in a fight can jump upwards. But where he jumps, and how he jumps, and how the enemy reacts to that movement, are all based on subtle use of the terrain; subtlety, I might add, that only works when the players' every single motions are important. When you give a player more lateral movement, he no longer has to worry about such small subtleties. Rather, he can figuratively "bulldoze" over the subtleties with a strong movement mechanic.
In other words, you can't easily simplify the low end mechanics, because the low velocity mechanics are the key mechanics for the vast majority of Tribes players. They fight in close duels, utilizing those low end mechanics very carefully, finding weaknesses in the enemy movement. When you strengthen these movement mechanics, you effectively remove the weaknesses upon which players rely to kill each other with any expediency. To be frank, Tribes weapons suck (by design). The disc launcher is slow (even in T2 classic, where it's relatively speedy), the chaingun's aim is difficult, and players are already moving in the sky. Without the weaknesses (quick peaking of the arc, predictable motions thanks to low air control, hitting and being stuck to the ground for a second as you impact badly), it becomes incredibly difficult to play the game with any subtlety.
While the new players will pick up these physics in the short term, in the long run, as they get better, the predictability of the players, and the use of the weapons, will get worse. In effect, jump-jetting will seem more like controlled flight rather than extended jumping, and veterans will see the skillful subtleties inherent to difficult control being eliminated.
That's my opinion on the subject. You can make low end movement somewhat easier, but you can't make it *that* much easier, or the players will simply be able to abuse the mechanics until the gameplay foundations--predictability and the weaknesses of movement--are partially irrelevant.
Also, I'd like to note again, just for the sake of posterity, that much of this is my opinion on Tribes movement theory, rather than experience with the effects of changes in T:V physics. I can't say what's *really* wrong until I can put my hands on the actual movement and give it a good testing. For all I know, the players in T:V are so motile that one can react to another quite easily, and the predictability issue isn't so worrying. Nevertheless, I feel that's a fine line, and will require a lot of tuning. If player's aren't "movement-weak" at some point, then the chances of them being shot by anything except the chaingun or sniper rifle suddenly decreases, possibly too far. In other words, I feel that players need to spend time feeling they have lost control, as they do in T1 or T2. The only reason veterans don't feel out of control when they have no control, is because they have the experience to make sure they fall correctly, rather than incorrectly, when they come tumbling out of the sky.