It doesn’t sound like we’re really that far apart on this.
You also identify that the way ammo is implemented currently isn’t very fair. Yes, the devs could raise the base amount of ammo enough that people didn’t need to use ammo crates (or they could remove the mechanic completely), or they could level the playing field by making everyone use ammo. All of those options are about making the disadvantage of carrying ammo less unfair.
And yes, cannons and missiles should hit harder, which is part of what they’re doing. If they just buffed damage and didn’t increase reload time, we’d probably be facing a really annoying cannon meta. Remember, the reload changes aren’t set in stone: it all depends on how things turn out in the test server. They may end up going with less of a reload nerf, or even more of a damage buff.
The advantage of using ammo as a balancing mechanism is that they can continue to let some weapons be capable of high damage, while introducing more risk in their use. And as I previously noted, ammo is going to help keep dogs and other close range builds from being too OP, as plowing into victims will have more risks and downsides.
The more I think about it, the more optimistic I am about the proposed changes. But then again, I’m into PVP and you are into PVE. The changes will play out differently for us.