Personally I hate having to scroll through each viewport and having the rest of the tank as a black void isn’t helping either but isn’t too bad. But being objective the time looking around with a scroll wheel takes is really long and for me at least it leaves me disorientated. A fix for this I would suggest is actually model the inside of the tank and the soldiers view in it. So your gunner would be standing in front of the sight fixed in place except for the head being able to look around freely and moving crewmembers could include a cool animation or something. While I don’t expect these anytime soon because the game is in closed beta it would be nice to have it.
in the Closed Beta Road Map, it says:

back in the day i got no asnwer when observation points were introducted,
( reffering to my older post: Obsveration Points - Free mouse looking )
but as i said, no answer.
for the issue regards, honeslty, and in my personal opinion, the gunner view points should be remain fixed, only the commander should be able to watch around just like a pilot in a cockpit.
but again, this is just my opinion.
anyway, so i wish you more luck than i had.
but i’m sure people will notice more as more CBTs will scroll newer posts ^^
and eventually, will end up reaching devs 
Cheers^^
lol yeah they are turning into the war thunder devs not saying anything and it’s worrisome but then again I can’t blame them for not saying anything.
agree, but I think it will come in full version.
I suggest in the meantime to give us a more efficient way of looking around the cupola instead of the zoom out/zoom in animation. instaswitching would be preferable.
For tanks with periscopes, give us an option to decouple it from the cannon direction, to quickly look around (though that might already be planned, I would guess).
kudos to Dark Flow on the open hatch update. Hope I will be able to use the binoculars with the Italian tank at some point.