I somewhat agree with you, except that I think the driver should have a small turret, and not be left without a turret completely as you're suggesting.

I've stated my opinion on this multiple times.

Separating the driver from the main turret is a massive buff that would only serve to make HAV's harder to kill and crush enemies easier than it does now. It'd remove the obvious blindspot created when a HAV is on the move, since a driver is generally forced to keep their turret facing forward in the direciton they are moving to prevent them running into stuff and/or getting stuck. If the turret can freely move, it becomes much harder for AV to coordinate and lay an ambush.

The fact is, the HAV is going to crush things no matter what, if the turrets stay as they are. If a second person gets the turret, not only is the HAV going to have more of an opportunity to do so. Sure, you'll get your wish in that it'll require two people to crush... Yet the fact that they crush and remain a 'win button' will still be an issue. At the risk of putting forth a strawman arguement : If you make the HAV require two people, why stop there? You mentioned the issue of 'forcing teamplay' in your OP. Realism dictates a tank has an entire crew. Should you -require- the tank to be full to make it more valuable to the team than just having the crew running infantry instead?

As long as the HAV can OHK pretty much any and all infantry, the issue of being a 'win button' will always be there. Perhaps a better solution would be to lower the base damage to slightly above those of handheld weapons but with a larger multiplier against vehicles to prevent them from being useless against vehicles with thousands of HP yet still able to hit an infantry without instantly killing him.

As stated countless times before : The main problem with HAV's is and always has been the turrets.

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If a tank has no passengers its no where near as dangerous. You're thinking balance is equal to numbers in the field, in reality its actually combat effectiveness you should be concerned with. A solo tank driver will be in trouble against two skilled av players. Or one solo tank. Or several militia swarms. Real balance is being able to quickly and effectively counter, and there are lots of ways to do this.

Making it obligatory for a tank to be fully staffed is not going to solve any problems, the problem is how players are trying to defeat tanks.

First off, its a HAV, its going to become balanced and hard to kill, theres a reason its called HAV. can you charge a protoheavy with a militia assault rifle while its wielding a "broadside" misomething something HMG no you cant.

Should swarms be as cover averting as they are now no,

should people stop trying to ruin vehicles in dust, yes.

In response to your first paragraph. Giving the driver a driving role, makes it a real HAV, if you cant compete against something thats just as balanced as your AV weapons and is now a fair, hard to kill vehicle with an elite tank squad operating it, than thats your gameplay issue. Secondly your gonna die to strong weapons its an HAV with a giant f**** blaster on it, everytime I die to a heavy with a broadside HMG or a protoforge, do I run off and complain, no because their fair and balanced and doing their role. HAV's are the underdogs and have everything against them, AV cover averting swarm launchers, av grenades, foreguns that do as much damage as a large rail gun and are much more mobile. Tell me once when you have had more than four or five things hitting you at once that were unfair as an infantry, you havent, you have some grenades, some sniper, various light guns and some forgeguns but you;ve been able to play time and time again without any worry in militia gear that cost nothing for you to run. HAV's dont have the luxury of BPO gear, so put some perspective into it.

Second Paragraph, its an HAV blasters are designed to almost if not competely devistate your infantry suit, Railguns are more anti vehicle, missiles are now area denial weapons/ long range supressive weapons. Lowering the Base damage to that of handheld weapons would make HAV's completely uselessl, its an HAV its supposed to be able to kill you. They already are damaging against vehicles enough if you know how to play them correctly and spend some time fitting your vehicle.

Third paragraph, its supposed to have good a good all around battlefield view, its an HAV, it has every right to be aware of all its surroundings at all times when it has so many things against it.

So I agree with the OP, minus making the driver only be able to move where the commander wants and making HAV's a crew based weapon will actually bring more fun into this game and make them less overpowered.