EmDo resources - differentiating them... is that a thing?

Ever since Eminent Domain came out, there have been people who were disappointed that the 4 resource types in the game are not more different from each other. While there are a few techs that reward you for either trading a variety of different resources or for specializing in one resource type, other than that Food, Water, Silicon, and Iron are equivalent.

This has never bothered me in the least - the resource type is merely a reflection of the type of planet that produced it. I could have used a generic "resource" token, but I opted for the more flavorful resource names and colors. I was a little surprised when people complained about that, citing it as one of the reasons the game was "obviously not finished" (the differently sized ship tokens being another such reason), though I guess I shouldn't have been.

When working on the first expansion to Eminent Domain, I wanted to address the complaints people had. As you can see in Escalation the different ship sizes have meaning, putting the complaint that "they're different sizes but all just 1 Fighter" to rest. I explored the possibility of using resource costs to differentiate the resources, but I realized that (a) tech cards already have planet requirements (which is the same as specific resource requirements), and (b) it was PHENOMENALLY painful to try and recall which cards cost which combinations of resources.

So I've been of the opinion that differentiating the resources is not a thing that matters at all, and I haven't tried to do it - with the caveat that in the future Oblivion expansion (the political agenda one), there could be agendas that reward trading a particular resource (again, that just rewards trading if you have a certain planet type in play).

Today I had an idea that may go along with those types of agendas, and focus on there being some meaning behind which resources you have...

In Escalation we have a Fleet tile, and in Exotica we have a Mining tile. Perhaps in Oblivion we can have a Market tile which allows you to trade one resource for another. That way, no matter which actual planets you have in play, you might be able to make use of those types of agendas. It could look something like this:

Market:
Action: Exchange 1 resource for another (store it in the same slot the traded resource came from)
Research: Spend 3R to upgrade to Improved Market

Improved Market:
Action: Exchange 1 resource for another (store it in the same slot the traded resource came from)
Action: Exchange 2 resources for up to 3 other resources
+1vp whenever you Trade [with a qualifier - like maybe when you trade 3 different resources, or when you trade 3 of the same resource perhaps. Or maybe just whenever you lead Trade?]

The thrust of Oblivion is supposed to be agendas and clout. Agendas are global effects that players can bring into and out of play via a new Politics role. Clout is like role symbols you can save up to be used later. I plan to have just a few techs in the set, dealing with the Agenda display and with clout. But I think there could be room for a Market tile in the expansion as well, to allow players a way to take advantage of some of the Agendas that have to do with trading particular resources, or potentially to use in conjunction with those few existing techs that reward diversity or specialization. Improved Market might be nice just as a way to produce resources as an action!

I like the sound of this, so I wanted to jot it down so I don't forget. If not a Market tile, I'd probably want some kind of Lobbyist tile or something that dealt with Clout or Agendas in some way. I hadn't really thought about that yet.