Awesome game! Thanks to those building the wiki as well.
Feature requests/suggestions. I am betting many/most of these are too complicated to implement, and obv you have no obligation to do anything more with the game that is pretty simple and already fantastic, but just putting them out there as ideas.
1. Manual zoom. I am zooming via the trackpad, and Ctrl+Scroll doesn't give very good control. I also have no horizontal scroll which is super annoying if I want be zoomed in.
2. Related to the above: a minimap. For telling me how much of the map I am not currently showing, as I struggle with zoom. Being able to drag around on a minimap would also fix the problem of (trackpads not giving) horizontal zoom.
3. Being able to save maps. Sometimes I want to experiment, and this would help. I like the previously made suggestion of a sandbox; but having saved maps might be easier to implement than would a sandbox, since the best map (and the null map) is already saved and available to restore and this would just be the same but with additional slots. But, restoring the best map, and clearing, are super useful to have, thank you for those!!
4. Being able to store "motifs" and use them like stamps. E.g., save some 3x3 or 5x5 square set of tiles, and then being able to use that like a "stamp" to make repeated copies of it. This would probably be pretty hard, but super useful.
5. Plots. I would love to have some visualizations over dimensions of {map cost, income, # of reduce tile cost upgrades, number of tiles used}. Having plots over time is a common thing I see in resource-management games, but I don't think that is super useful in a game where the map can be easily cleared. Or, maybe raw data downloads so we can do our own summaries and make our own plots :).