If possible, resources should cluster around one location rather than being found evenly throughout the map. This would instigate wars over resources, an idea which I really like. It would also require you to choose your city sites carefully if you want to go for higher-up Monopoly buildings (if my proposal is implemented, that is).
That is down to the function(Bonus Resource Distribution) I am using in AssignStartingPlots.lua, its unrestricted to layers/regions(Strategic/Luxury), to put it simply I used the function that caused me the least bit of trouble in debugging to get the resources on the maps. WHen it comes to Regions like you want it gets a whole lot more complicated and easier to mess it all up(still doable but 9/10 times alot of debugging rewriting code ect).
Edit:
Its probably easier to make our own Layer than go messing with the static regions/layers and set our restriction within said layer.

the alien head Icon does look cool
For the new resources like Flax and Rubber, is there a building that interacts with them, are they luxury (could see that for a few of the new ones), or are they just there? And for the resources that are really similar (Barley and Wheat, Exotic Hardwood and Oak), is there any way to differentiate them? Again, are there buildings/units/wonders that make use of them? Right now, they seem to be added in as strictly bonus resources.