This idea has been stewing in my head for a while, and has only recently come to the front burner, so to speak.

I want to start by recognizing that not everyone is going to like every game. People have their preferences, and so it would be ridiculous and unfeasible to try to force everyone into a certain type of game.
However, I am proposing a game that would combine many different genres of game into one, not forcibly so, either. It would be an MMO space game, but would essentially incorporate elements of multiple genres into the efforts of a faction toward an end goal. For example, a faction would be overseen (oversaw?) by a 4X player who would guide things generally, such as diplomacy, production, research, etc. Space battles would be conducted in the Space RTS style (in my mind, like Star Wars: Empire at War). Planets, or more specifically, cities on planets, could be built/goverened/maintained by a SimCity aficionado. Ground battles would be conducted by traditional RTS players. On the ground itself, however, the FPS players could vastly affect the tide of a battle, much more so than an AI-controlled soldier under the supervision of the RTS player. Research for a faction could be boosted by players playing puzzle games. Those who prefer space flight sims like Freespace would have fighters available for flying within the scope of the space RTS. Every facet of play (FPS, RTS, 4X, etc) would affect at some level every other facet. The working factor is that you'd have to trust those on both the "higher" and "lower" levels to know what they're doing, since the higher levels can't directly control you, but perhaps they can see something you can't. The "higher" levels have to trust the "lower" levels to do their task better than the AI could.

I guess the question I'm really asking is this: is such a game even possible from a market perspective? I've dabbled in many of the different game genres, and sometimes I find one too tedious when I've played it for a while. Then I have to switch games entirely and lose all progress, like I'm starting entirely anew. From my perspective, being able to still contribute to a faction regardless of what I'm doing (4X, puzzles, RTS) would be a great thing. What are your thoughts on such a game? Would you play it? What other genres could be incorporated into the game? Is it absolutely impossible from a technical perspective, or do we just have to wait for better technology?

Thanks for your time and attention

This idea has been flung around quite a lot. Keyword here is: complex. As in "making this kind of game is enormously complex".

I would probably play it, if done right. But chances are such a project would suffer from overreach and feature creep and, in time, would just horribly fail. Also, how would strategic-tactical perspectives merge exactly? A 4X player doesn't exactly enjoy having his units disobey orders, or go wandering off on their own because they have "better things to do.." - same goes for RTS players. And don't even get me started on what someone playing this as an FPS character would think if he had to wait until an engagement became available.
In the end, this is all solvable from a game design perspective. The real question then becomes: how do you manage such a game without it becoming a gigantic juggernaut of fail?

The strategic-tactical perspectives would not merge seamlessly; from a technological and gameplay perspective, that would be near-impossible. Instead, there would be "slots" for a particular position, say, the commander of a region with an RTS perspective. The higher you go, the fewer the spots and the less likely you are to be able to get to a spot. That being said, the "higher" levels also require much more human supervision and can't be abstracted by AI nearly as much, so there's a much higher demand which can make up for the fewer spots. Switching perspectives or roles would not be instantaneous, just as you couldn't instantly travel from HQ to the frontlines instantly.

As for the interaction between "higher" and "lower" levels, the fact that not all of your units obey you is actually a crucial piece of the game. All the AI-controlled units, would, of course, do exactly as you say, but you have to balance the increased benefit you get from good human players with the fact that they might not fit into your grand scheme. It's a balance every military commander (particularly naval ones) have to balance; between autonomy and expertise on the low levels and cohesion on the high levels. This would, I think, be a much more accurate representation of a "real life" war scenario.

You're absolutely right about having to wait. I imagined at first that the number of people involved and the size of the galaxy would essentially mean that there would always be SOME engagement raging, but you make an excellent point, especially in the early pieces of the game where each faction is sort of getting its footing and probably not fighing a whole lot.

To this end, I suggest "simulation" battles available, similar to playing against the AI in an RTS as opposed to multiplayer or the campaign mode. It would be instant action, and would count as if you were simply playing it in a simulator in-universe; no huge losses from losing, no huge gains from winning, but it would be a facet of one's reputation which would increase the chances of being respected and/or hired by a faction. You wouldn't have to wait for a "real" engagement to get going on any level, and puzzle games could be done all the time. It could also be multiplayer, like if you wanted set up a little 4v4 deathmatch in FPS mode.

Pong, Tetris, Solitaire, Minesweeper, Peggle, Farmville...

Or are you only talking about something that would appeal to hardcore gamers of the various game genres?

Mostly I was referring to genres of game, like FPS, RTS, Sim, Puzzle, etc. From what I'm understanding, you're suggesting classic arcade-style games. I'm all for it, but I can't see how they could contribute to the overall objective of a faction. Got any suggestions?

Since every "minigame" would be worse than a full game of that genre, no, I wouldn't play it.

It would also cost a fortune to make and no one would fund it.

Scope! It's not just mouthwash.

The game as I envision it is designed to appeal to gamers who want to play multiple games of different genres but only purchase (or open) one. And while it probably wouldn't be able to match the giants of the respective genres, the appeal I believe is in those who enjoy multiple genres of game and might like to see their efforts in the different areas contribute to a single endgoal. So while the RTS section may not be as great as Starcraft, it would have a 4X or FPS element that Starcraft could never have. I dunno, I find this to be an attractive prospect.

I'm also attempting to gauge whether or not the idea is even worth pursuing. I don't imagine it would be easy or cheap, but if the demand for anything is great enough, there will be funding and there will be effort. I'm pretty sure WoW costs hundreds of thousands of dollars to run every year, but it is still one of the most successful games of all time. I'm just wondering if the demand for such a thing (which would appeal to multiple genres of gamers) would be enough to justify the time/monetary cost.