So the strongest dps classes here are scout and mage?
Yes
Are there no one above or simply equal to these two?
Single targetwise, no.
In aoe tho, Yes bard, but that's about it.
Do they often top the dps lists in raids and such?
Raids are MOSTLY, not always, focused on single target dps'ing a boss while doing tactics to stay alive. So yes mage/scout are the top dps in single.
Bard has insanely great dps both in PvP and PvE. Also Melee Priest has good amount of damage in the right hands.
Bard is not a bad choice at all either, offers decent (not best) potential dps, but also offers a great support aspect of gameplay that benefits your whole team/raid.
Melee priest is very strong in aoe, perhaps equal to bard, but single target of healer is disappointing
Hope this helps!
Feel free to ask more.