I agree on the point that if you constantly swings the camera around, it gets better.
But I can't agree that is satisfaing solution.
With more than 700hrs on ST and more than 600hrs on MR, I consider myself as a quite expirienced player so take me seriously on this, I'll try to explain.
Camera works well, when you swing it around to reduce blind spots which are plenty. Looking by 3rd person camera over a huge truck, those blind spots are given and can't be helped.
Problems are camera restrictions. Game tends to workaround this, by wide-opened relatively flat maps, but if you play custom maps those contain quite steep slopes, you can see the issue. I can't count, how many time I was frustrated by the fact, that I can't turn camera in THERE to see why my truck can't go any further (usually a tree), sometimes I have pain in the neck, because I unintensionally lean my head backwards to "see more up there", because looking-up is also restricted. More zoom out could be very helpfull, because I like to ride 8x8 trucks (stock game or from WS) and from some angles I can't even see whole vehicle.
Not to mention situations, when restrictions from several sources interfere with each other (camera can't go under the water, can't go underground, through object,...). Usually I end up with camera ridiculously zoomed IN, and I can admire one of my tires, but that is all.
If you are playing on keyboard, camera is actually "better": you have your left hand on WASD, right hand grasps the mouse, you can swing the camera as comfortable as possible (under mentioned restrictions).
I am using G25 with shifter and therefore I have no spare hand to constantly operate with camera, using mouse is inconvenient, because each time I have to realize first "where am I" and only then I can move the camera where I want it -> too long for actual use. There is a D-pad for this on a shifter, but that is less usefull than mouse is and I can't sacrifice a hand just for that constantly. That've been said, I usually drive with the camera in some "as good as possible" position and time by time I stopped and rearange it. Or swinging it by D-pad but that is rather uncomfortable and spoils the expirience.
Surprisingly, a lot of these problems was "solved" by unlocking zoom restrictions by ST+ back in old game.
As you might remeber, I was "going through" engine+gearbox issue in "truck lua" topic, So I just remind base idea: by me, game needs "real-life-like" propelling system, current solution is acceptable, as long as you play on keyboard (if AT changes gears reasonably), but as long as this game is considered as "driving simulator", using wheel with pedals and shifter should be considered as common. And for that, current solution is far from perfect.
Jeez, I wrote a lot again, I hope that my english is understandable...
P.S.: I am quite missing camera from ST: instead of cockpit, there was camera on the roof - much wider field of view