The idea here is that periodically (either per time period, like day; or when you buy a specific upgrade) you’re presented with a problem in your kingdom and a few ways to solve it. The solutions should be active, like building a certain number of a building, spending coins, “charging” a magical object (via a temporary spell), sacrificing your upgrades and buildings, etc. Each successful solution unlocks a trophy (with associated upgrade), and you are only given each issue once per game (or per reincarnation). Issues would have to be altered to fit to current alignment or locked to specific alignments.
Example: My liege, a dragon is attacking your Elven villagers! Do you build magical armor for your best knight (mana charge), build up a huge army (knight barracks), or pay it off peacefully (with a coin value set perhaps by what 100x of your most expensive current building purchase would be). While the dragon is attacking, all your production is reduced and you will occasionally lose one of a random building.
Someone suggested this a while back and I thought it was a neat idea. It’s basically a type of prestige upgrade that improves a certain feature of your kingdom — so having Mountains might improve all of the building types that are associated with mining and mountains, for example. My take would be to have it be a three-stage process: The first time you build on a particular land type, you are an Expedition, and suffer a penalty; the second time you are a Settlement, and suffer some penalty but also have a bonus; the third time you are Native and recieve the full bonuses. Each new game, you can go back to a land you’ve already settled or start working on a new one (but you can only pick one land type for the game).
Exchanging gold for full mana at an increasing cost each time you do it. Helpful for those of us who don’t actively play for long periods of time. (It would be interesting to offer “trading” of other sorts as well — like spending gold to increase your clicks for that game score or your game length — but that might be more problematic.)