Ok heres some thoughts on the game plus some ideas for the game
Firstly, the spike tracks should be toggleable insead of having to hold the shift button. Secondly, there should be a way to recover your tank if you get it stuck because i got my tank stuck on some bits of destroyed building. those are the only things that really bothered me.
Now for the ideas i have...
1. Fuel/ durability system. You'll have to worry about running out of fuel, this could be mitigated by fuel tank upgrades and extra fuel canister upgrades that attach fuel can holders for emergency refueling. You'll also also have to worry about breaking your tank if youre too rough with it, this could be mitigated by upgrading the durability and repair kit upgrades for on the go repairs! Both fuel and tank health can be replenished at settlements for a small fee of around 100 dollars. This mechanic should be able to be disabled if the player wants an easier time.
2. Environmental/ weather hazards. Different hazards that pose issues for your tank. Deep snow can slow you down to a crawl and could possibly get your tank stuck. Thin ice could make crossing ice lakes trecherous, meaning one misstep could leave you sinking into a watery grave. Lightning storms could damage your tank and disable any electronics like the radar or the headlight.
3. Different upgrades. Different types of upgrades that have pros and cons. For example an upgrade that converts your tank to an electric drivetrain that has the pro of increased acceleration, torque, and efficiency, with the con of less top speed, heavier weight, and slightly more expensive recharging costs. Maybe it opens up an upgrade path that lets you put wind turbines on your tank so you can passively regenerate battery charge when its windy.
4. Alternate tanks. Different tanks for different playstyles. There could a lightweight fast tank modeled after a snowcat with less storage space and better fuel efficiency. And maybe a large, slow tank with a lot of storage space but its slow, cumbersome and it eats through fuel. Maybe throw in some fun vehicles like a snowmobile
And thats pretty much all the ideas i have.