Do try Populous 3. It’s old enough to run fast even in low end computers, yet the graphics are so nice and pleasant. But beyond that, it adds some elements to RTS gaming which I’ve found in very few other games.
For starters, all the maps are spheres, instead of the good old tetragon of most games or the “cylinder” of Civilization. That adds a whole new level of challenge for erecting your defenses, since the enemy can just go the other way around the world to get you.
It’s got the simplest user interface I’ve ever seen on any strategy game. And a lot of things in this game make more sense than usual. For example, destroying buildings. In most games your units hit the exterior of buildings, you can’t even see them connecting their hits, and then the buildings catches fire out of the blue and finally blows up. In Populous, your guys actually enter the building, and start punching/kicking/pushing the walls and the structural frame, and you can see the building shaling and pieces of it falling down as it is vandalized. You can also see flying debris if something like a meteor hits a building, or when it’s torn and ripped apart by a quake, and nothing is as eye-cathing than seeing a tower spinning on its own axis as it tilts and falls on its side in a lake when you remove the ground beneath it with an erosion spell. If you still like seeing buildings on fire, though, go ahead and cast lightning on them. Or meteor shower. Or volcano, close to them, but this way they’ll burn too fast to be cool to watch.
It’s fully 3D, not just for graphics but for game mechanics as well. When a fight starts on a slope, sometimes a unit will lose balance and roll all the way down the hill (this causes damage). You can shape the world with spells such as earthquake, erosion, volcano, land bridge etc.
Here’s a video of a guy playing the first level of the single player campaign:
edit: and here’s a video of a guy using the earthquake spell a lot:
By the end of this video the guy casts volcano, one of the most impressive spells ever.