What I like the most in a RTS is: -Realism. I just love the planes in Empire Earth or Sudden Strike II or Total Annihilation, but I hate them in Starcraft or Star Wars GB, think why. Other realistic game is the Cossacks/American Conquest saga, the most realistic ever. -Eyecandy and variety. I like a lot of different units, lots of eyecandy for terrain, lots of scn editor stuff, that's what I like the most of SWGb for example, and AOK in its day. When I open the scn editor, if I think "wow, there's a cool stuff here to make scenarios and such" that's a good thing to like the game. -Easy and addictive. I dont know why but some games have a feeling that makes them to play more and more: AOE, C&C, Red Alert.. there seems to not be more of these games anymore, though... that's why they are classics -Epic and good story. C&C with its gruesome quantity of cool videos made me feel inside the story. I love epic plots, such as C&C's , and though it's isnt RTS: Baldur's Gate II, almost LordoftheRings-ish -Memorable units/buildings. Ahhh, the AOE hoplite..the Red Alert attack dogs... Starcraft siege tanks...the C&C obelisks and Orca bombers... see what I mean?