Yeah, you should add idle mechanics to this always-online single player game so that players can hack into enemy computers and mine bit-Skell with the GPU. After all, Skell credits being crypto is already part of the game narrative. And then you can sell mining boosters at the store so that the most elite special fores soldiers can mine even more Skell by idling and not playing the game at all.
You should add rocket jump specialty with +95% explosion protection so that the most ultimate special forces agents can rocket jump over enemy fences and even jump straight into flying helicopters to seriously confuse the enemy.
You should add a grappling hook in the store so that players who want the ultimate soldier survival experience can choose to buy this amazing hitech survival tool in order to more quickly traverse the vast terrain without having to deal with all those sentinel soldiers whose bike broke down.
You should add the special forces ability to fry marshmallows at the bivouac for morale boost. Or you could sell morale boosts directly at the store.
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On a more serious note though. You could add misfire mechanics to weapons. If the player roll around in the mud too much when hiding from enemies and drones, their guns might misfire. One primary rule for soldier survival is to maintain their weapon and gear, which they could do at the bivouac. But the fact that the soldier also simply could switch out their misfiring weapon with one of their 1000 guns they are carrying in their cosmetic backpack, kinda breaks immersion.