There was a replacement icon sprite pack that Thygrrr released ages ago. It wasnt a mod, it required you to replace a bunch of files in your supcom install. And yes, I mean the icons on the map.
The icons were just straight upsized, so they are rather pixelly, but if the normal icons are too small they should look fine.
I can't find the link on GPG forums anymore, so maybe you can ask Thygrrr directly to see if he still has it, since he's still around over here.
I guess, along the lines of "Things SupCom should have had in the first place", it would be nice if this was included with FAF and made integrated/switchable somehow