Connecting minecarts with chains and copper chest in minecarts.

So I saw a suggestion for leashing minecarts, which I thought was a great idea and got inspired by it. What if we could connect minecarts using chains. I think it would look great and be useful. We could also add copper chests in minecarts, so the copper golems would empty out the chest from the minecart. For example when making a golem the chest that it spawns with could be crafted with the minecart making a copper chest minecart. Still tho I have a problem. How to stop the golem from going to that minecart with a chest all the time? Maybe we could add a special type of a rail that only, when the minecart with the copper chest is on the specific rail, only then would the copper golem be able to interact with the chest. But that's just my idea. In summary I think this could be a great idea not just for decorations, but also used for quick transportation of items to the copper golem to sort those items out, while we are in the cave for example. That's the idea I have with minecarts. Thank you!