What if other players could go to your colony, buy plots of land and place buildings there like mines. They would own and operate the buildings by themselves, and you would just tax them to make a profit (so for instance if a gold mine makes 10 gold, you would take half of it to use in your own colony). This way older players can help new players without handing them billions of resources like that. Down below are some ideas on how this could work.
Bonds: a colony can issue bonds to collect money and finance projects. Bonds are certificates that guarantee lenders will get their money back plus interest in fixed payments ( like in real life). Once you issue a bond, you must pay it back on time or else the lending colony can foreclose on a significant amount of your buildings. Also if you dont pay back a bond your credit rating will go down making it unlikley any other colonies will loan you money.
Private property: plots of land that are inside your colony but owned by another player. Your laws still apply in these areas, but you can't build on them without permission of the owner. If you want to build a massive building however, you might be able to use eminent domain to reclaim the land, but you will have to pay the other player a minimum amount of money.
Corporations: organizations owned by multiple colonies whose sole job is to make money for their owners. Corporations will take money from all their owners, pool it together, and use it to invest in other colonies. Corporations are useful for small colonies as they allow them to pool their money together and compete with the giants.
Corporations are taxed the same as individuals.