I couldn't find this on the "already suggested" post. But I think there should be a limit on how much weight you can carry in your inventory. It's unreal that I can carry 10 vehicles, and 10,000 parts of Iron, and 10,000 parts of Gold, an entire colony of buildings etc etc.
I think a weight needs to be assigned to items, with a character only being able to carry so much. You can design your vehicles to have a storage container on it, and maybe have 3 different sizes. This way you need to cart what you transport using a vehicle.
Mining : If I want to go mine out an iron deposit, I bring a vehicle with me with a storage container on it, get out and start digging. You have to stay within a certain distance of your vehicle, so that anything you mine with a shovel or pickaxe automatically goes into the vehicle's storage container, and not your personal inventory. If you end up out of range of your vehicle (digging too deep for example), then the mined materials start filling your personal inventory. Once your personal inventory is full, you need to run back to your vehicle to transfer it, and then repeat.
Building at the colony: When building your colony, all your materials should be stored in the colony storage box which has no limit. When you start building things around your base using dirt, marble, steel etc, the blocks come out of the colony storage box. This could be limited by either the assembly hub's sphere, or maybe a second larger sphere that lets you build slightly outside of the bubble.
If you want to built small structures or towers elsewhere away from your base, you can either use a vehicle's storage container, or your limited personal inventory of what you're able to carry.
Vehicles in inventory: You shouldn't be able to put vehicles in your inventory unless their storage container is empty. However, since I'm aware that sometimes your vehicle flips over or gets stuck, you need to put it in your inventory and drop it somewhere else. So maybe you CAN put a vehicle in your inventory with full storage, but when you do, you walk very very slowly and can't fast travel. This still allows you to move your vehicle to get out of a glitchy situation.
This would turn the game into something much more interesting because you have to set up some logistics to get things done. Lets say there is an island that I know of which is full of gold and silver. I will need 3 vehicles. A truck to get from my colony to the shore, a boat to get across the water, and a truck for the other side (Or possibly use the same truck by bringing it with you on the boat). Get to the island, mine all the silver and gold, and truck it back to shore to your boat. Transfer all the contents from the truck to the boat, sail back across the water, transfer back to truck and drive it to your colony. This feels more like something is accomplished. Because right now I can go to that island, put my vehicles in my inventory, mine thousands of blocks of gold and silver and then just fast travel back to my colony. Kinds of feels cheap there.
Well that's one of my ideas. I have several. I love this game, and I think some simple changes can make gameplay more interesting and fun.