RTS games are kinda pointless unless you have online play, and imo are horrible in 2D, not to mention incredibly complicated to make.
For online, this is true but thanks to SciDave's online plugin there is starting to be a point in making one.
Command and Conquer was best before it went 3D.
They are complicated to make though, this will probably remain true when making a good RTS is attempted sadly =/