I was terribly impressed of how best results comes out from a fully crewed tanks.
Most important things I've reported about having a full crew:
1) you know people, and the more you practice, the more you learn about them, (this one alone is enough fullfilment for me from a game )
2) you will fully understand and will become VERY good in your stations in just few months, because you will level your tecnical knowledge to the best player in your tank, and usually VCs & TCs are very skilled persons.
(e.g. yesterday night in a pretty difficult scenario, i've got 7 kills with 90% hit ratio and 7.9s time to target. this is not only because i'm better, but because in our team we are becoming fully cooperative, and so driver knows exactly what commander wants and when gunner's barrel will be out of the ground, gunner knows procedures very well and will help commander to focus on situational awarenes more than scanning around, and tc will say "gunner sabot tank!" and in less of 9 secs you will be able to hit that target in the right place in the right moment, and possibly, one shoot one kill, while driver will bring you out of LOF when reloading, or will look for a retreat route without killing any members into trees.
3)Comms are A LOT OF FUN, seeing the thing work perfectly and have a clear concise comm with you tc and driver is actualy very very funny and immersive in my opinion.
Basically: I'm training as a commander, I'm perfectioning my gunner skills, that thanks to my guys it's become perfectly high, and i also love to drive sometimes to have a complete knowledge of my gun truck (even if - believe that or not - driving it's still hard to me, on driver depends the life of the tank itself. (p.s. driving position in leo2's it's very detailed and the rear view camera allows you to make a lot of rambo moves in backup gear, so as it's exciting in the cv-90 cuz you can have the gunners sight under your eyes and find a better hull down/turret down pos)
Always speaking for me, i'm available to be a driver if needed, and it's not a second choice!
So if you're interested in doing the things as close as possible as RL, join our multi crew group (training almost always when time permits) and think about every position.