Dawn of war
you really cant turtle. this makes it more beautiful than your average RTS, and if you can turtle, than your opponents just aren't imaginative enough (drop pods, orbital bombardment, or my personal favorite, send wave after wave of necrons then mass resurrect them all in their lines)
admittedly, you can turtle against bots, but its usually suicidal, unless you play tau, get enough power resource flooding in (12 generators on tier 3 power production) and you can make a never-ending stream of distraction robots (drones), and then send a team of jump infantry (commander, stealth suits, crisis) to infiltrate and blitz the base. any other race, you get bottled in, and overrun
However, after DoW2 comes out, stop playing, because there will be tyranids, and then there's no point playing, we all know who wins. Bugs4life
what was i saying? oh yeah, DoW, apart from just being pretty, it does'nt suffer from alot of problems that other RTS's have, its fast, fun and futile, because nids will eat you