Dungeons aren't the only reliable source of exp. I've leveled all of my DPS classes from 1-50 with FATEs and levequests for the most part. The only time I've really done dungeons is when I'm leveling with friends that are leveling tank/healer. The queue was already bad before Rogue was introduced, and I didn't want to deal with it. This isn't something that SE can just wave a wand and magically fix. The fact is, way more people want to bring the pewpew with a DPS character than want to play support as a tank/healer, especially now with a new DPS class being released.
If you want to main DPS, you end up having to deal with sucky queues. You mayaswell get used to it now. :/