In fact you are all right in what you wrote.
Metal tracks, wheels etc, do give a better performance outdoors, may last longer, but do cost some extra money too to invest.
But it all depends on what you want to do with your tank, I mean are you an always outdoor driver, or just occasionally?
I do own quite a lot of tanks, most are Taigen metal versions, but I also own quite some HL plastic ones.
Most of the time they are all on the shelf, and from there it makes no difference at all if it's a metal one or an all plastic tank.
The plastic ones I mostly use as some kind of deco in photoshoots, and with some aging and weathering they do not look that bad at all.
The advantage of an all plastic one can be, that you can upgrade as your finances allow it, in the beginning they are cheaper than a metal version, but in the end you might have payed quite some hard earned cash more, than if you would have bought a metal one in the first place.....but as I mentioned before, it all depends on what you want with your tank.
I also prefer the plastic turrets compared to the metal ones, which do not add anything extra except the weight!
Also with plastic turrets the maingun is not wobbling up and down as much as when you have a metal turret. I do have some KingTigers, all plastic but they do have a metal maingun. The mainguns mostly stay where they are during outdoor rides, when I compare that to my metal Tiger 1's, their guns move quite a lot up and down.
But it is all everybody's own decision what to do, what to buy, upgrade or not upgrade, outdoor or carpet driving, most important will be the fun of modelbuilding and making the tank your own.
I do like both versions, metal or plastic.
For example, this is an all plastic KingTiger:
And this is a metal version Panzer IV with home made metal Schurzen, messing brackets and much more:
As I said, on the shelf there is no difference at all.
Rob.