1: Capture of enemy supplies happens very rarely, usually in cases where the player losing the truck is already losing badly. Also, the capturer may or may not actually need any supplies at that time, while taking the supplies from the enemy, be it by kill or capture, is on average the more impactful effect because that truck is almost always called in to answer to a specific need. For those reasons, I find it to be a rather irrelevant aspect of the game, close to the bottom of the priority list. It happens that you capture an enemy truck and it's nice to have, but it's not really a big deal.
2: I agree on this, it would be good to have a more distinct and realistic difference between light supply cars and big supply trucks. Of course the lighter cars should then also be a lot cheaper and more numerous to balance it out. However, again I would place this pretty damn close to the very bottom of the priority list for changes to make. Game must be in a pretty good state for this to be a relevant discussion.
3: No, no, no, no! First of all, the argument of realism is false. Supplies aren't usually brought up to an active front line at all, the common procedure is for the troops to rotate back to supply stations to get resupplied and then return, because obviously a big truck with weak off-road ability and filled with explosives showing up at the front and gathering a platoon around it is a really good way to reveal your position and get mortared. In some cases supplies are brought to the front, but that would mostly be during the night when no fighting is going on (thus not in the scope of this game) and only the supplies specifically asked for will be brought forward. Not as specific as exact number and type of caliber, rather "small arms ammo", "food and water" or "clothes", but there sure wouldn't be a truck half full of artillery shells coming up the the foxholes and ask if anyone needs to top up their water bottles. In those cases the current system is actually more representative than what you suggest, since the supply will all be of the type requested. Main point is still that supply trucks on the front is unrealistic anyway, so why make a fuss about what it's carrying as if that's going to be determining whether it's realistic or not?
Secondly, I do not see how this would make the game more fun. More mechanics and more things to memorize and think about should only be added if it genuinely adds real depth (not the same as number of mechanics) or significant immersion. I established already in the paragraph above my argument that your proposed change would not add to realism and immersion, and I do not see how it would add meaningful gameplay depth. Will it enable new strategies? Will it significantly affect the diversity of unit types? Will it change how battles are fought or improve the meta-game? Again; my answer is "No, no, no, no!".
) stolen gas/petrol makes perfect sense, as no repairs are allowed incompatible spare parts are out of the question.
