If you could change AoE II to your liking, which feature would you add/change?

I'm collecting features for a wishlist, what should be changed or added to the Gameplay or UI or whatever for an AoEII-Game? Start to dream, everything is possible, some examples:

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• a rolling relic for the battle field with a ranged attack bonus for allied units
• renewable resources, animals repopulate as long as there are at least 2 of each kind on the map
• roads on commonly traveled areas allow faster traffic, trade spawns stone roads, the longer you have a trade line up and running, the faster your trade carts are
• Buildings can be deconstructed to recover materials, slower than just deleting/destroying it, but leaves a salvage pile behind. salvage dimishes per time. resources can be harvested by villagers on a higher rate.
• a new 5th "free trade" age where allies share resources, with massive battles happening

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What do you people have in mind? Dream!