Are there any games that have players controling different slices in the same space, like one player controls economy, another player controls production/R&D, and a 3rd player controls tactical?
So a few RTS games (StarCraft 2, Steel Division 2 come to mind) allow multiple players to share control of the same units/resources so you could artificially divide up responsibilities. You need to go far away from RTS to a game like Artemis: Spaceship Bridge Simulator to find a game where players are dealing with distinct gameplay to a common goal in a shared space however
Actually, I was just playing AoE2 (the original from 1999) last night with my family and discovered this feature.
When joining a multiplayer game, you can choose player number and team. If you choose the same player number and team as someone else, both players have control of the same units.