My dream game is a mix of 4X, RTS & open world FPS.
Let's call it Civilize & Conquer & Cry—hey, CCC, I like
The starting 4X local map offers a few choices of sites for cities and outposts—El Presidente selects objectives.
Switch to RTS mode where the job is to establish those objectives while dealing with competitors along the way. Okay, valley secure—Generalissimo picks a likely direction for expansion.
Now into FPS for Rocky Recon to clear out the opposition in the direction we want our troops to go, and achieve some tactical advantage—eg high ground or capturing a radar post to expand the map, or an industrial center to boost resources, or a lab to boost research.
The map is procedurally drawn so there's infinite replayability, there are multiple victory conditions, the 'good stuff' is available early on if Presidente or Generalissimo chooses to go for it.