It kind of bothers me that in the Civilization series the improvement for strategic and luxury resources requires no extra mental effort. There is always only one possible building for each resource. The same seems true for Endless legend – I've just checked the wiki since I didn't play the game. It would be more interesting and better integrate these resources into the overall strategy if there were at least two different improvements to choose from. For instance, silver can be used to create nice looking jewelry, which increases population happiness, or to mint coins generating an additional stream of cash. Are there any information yet which kind of resources will be in the game?

PS: One caveat I can see with this more flexible approach is that the resources may lose there uniqueness if there are too many options to choose from, that repeat for every resource just under a different name.

There is plenty of options already with resources, especially in Endless. Strategic resources are stockpiled and can be used for stronger weapons or armor for pretty much any ship if you have enough, or you can use them for certain buildings or wonders. Luxury resources can be used for quests, and depending on the game can have other effects, such as increasing certain population growth rates or spending them to create empire wide bonuses.

In Humankind, I could see things like Iron allowing you to make stronger weapons early game, and eventually being needed to make most ships (along with techs that give you buildings that make it without having to mine it or make it much more common so you don't have to worry about micromanaging the metal sources). It would be interesting if you (or at least some cultures) can get stars, or at least fame, for getting new luxury resources that don't start anywhere near you.

My problem with this is that you can delay the decision what to do with your iron until the point when you want to build your ship or a super-fancy hammer. There would rarely be a scenario where you won't build the mine/extractor on the resource since it is almost always worthwile to go for that only choice. Maybe I wasn't explicit enough, I am especially concerned about having only one building per resource and not having to make a long-term commitment right from the start of collecting it.