This idea has been nagging in my head for years. I've played Age of Wonder II, I've played other Fantasy RTS games, and while I've enjoyed the experience a lot, there is something.. that lacks.
How it is that when you play the elves, you start at the same time than the humans. You start at the same level technologically / technically than the humans? It's not logical. in typical fantasy, elves have been around for MILLENIA when the first human kingdoms started cropping around. Same thing with dwarves!
First, imagine a game a little like GalCiv in term of basic gameplay, but with a fantasy-touch. You play human, and the other civilization you are in compettition with are also humans. You are on the same starting footstep than them, and you can either develop your technology, or your magical powers. You can create a slave-empire, or a Higly Honorable Knight tradition (like Cormyr), or a Magicocracy (like Thay), evil or good. Each game you play can be different in the way you make your humans evolve. A true sandbox civilization.
But when you play human, and you first explore the world, you encounter the other human civilizations, but you also encounter some non-human civilization, like elves and dwarves. Think of them as "minor races" like GalCiv, but within gameplay view, they have been around for WAY long than you have. Their technology and magic, their tactics and armies are already at their peak. You know it's in your best interest to leave them alone. They would crush you like a bug (like the Dread Lords) easily..
... for a time. Because, as you grow, you can become interested in their riches. Their artefacts, their loot! They are more advanced than you, perhaps, but as a human nation, you are WAY more numerous than them. Over time, maybe you could form an alliance with other human nations to conquer them?
Or, will they make you their favorite civilization, and shower you with gifts to help them defend against the other human civs (like Bretonnia or the Empire?)
And, after you finished a game with humans, you could play as the Elves. When you begin, only other elves civs are around, and your population growth is quiiiiiite limite. Over some time, suddenly, the Dwarves appear in mountain (where you can't really put cities anyway, so you don'T care. Or you extract them tribute?)
Eventually, when you reached some level of power, human nations start cropping everywhere! They are pitiful ennemies, perhaps. But for every one you crush, 2 more appear! And if you kill 100 humans for every lost elf, it's a NET WIN for them?! You have to rely on stealth rather than brute force, until.. (put end-game condition)
You can also play as the dwarf. This is a nice gameplay for a turtle-like player. You live in the mountains, and no other races are interested in those, so no competition - at first - But the orcs keep on coming, and trying to conquer your stronghold. Only the elves exist at the time, maybe you can try to ask for their help? Or divert the orcs against the elves? Eventually, human nation also start cropping around, maybe you can help them develop technologically to enlist them to your defence?
That's what I would like to see in a Fantasy game. A different gameplay, with a different time scale between fantasy races. You can play 100 games as the humans, and customize your empire as you'd like, you'd have 100 different games. But if you switch to elves, you simply CHANGE GAME, and your priorities shifts, and you see things from another point of view.