Ways to renew resources by trading and/or improving farms

As we have seen in AOE II, we always could keep the match going by trading with our allies to get gold and then buying resources. It got better in AOM where we could have permanent farms apart of being able to trade gold. In this edition I would suggest that we could have ways to make the game more competitive by increasing our production.

Also, it would be really good if we can increase the population limit and with that increasing maximum selection of units

I would like trading resources to be kinda premanent, not going ups and down to like…20 for 100?
So if you buy wood it should be 100 gold for 200 wood or sth, not change.
This would make the game more interesting imo.