Guild Wars 2

What is the role of a D/D Elementalist in the following situations?

1. Dungeons
2. WvW Siege Attack
3. WvW Siege Defense
4. WvW Fighting with Your Zerg
5. WvW Fighting against a Zerg

I have a level 20 elementalist and a level 20 thief, and I am trying to decide which character would be more fun to play with.

1. buffs/heals/aoe damage
2. You pick up a staff and sit there doing stuff (cast spells, combo fields, some healing)
3. Same as attack. Dagger is pretty useless in both situations.
4. Group speed boosts (Zephir’s Boon, shared auras), ability to catch pretty much anything (including thieves) and slow them down for your zerg. Or charging through to enemy back lines and generally pushing the enemy back. General boons/healing/condition removal as part of your normal damage cycles (ok you have to do slightly more to dish out maximum healing but even an attunment change, dodge roll and 1 fast cast is a good chunk of healing).
5. Good aoe damage, survivability and escape.

I play an ele and have only a low level thief myself so my opinion is biased but the way I see it is, I see very few reasons to bother playing my thief as ele is just superior in general.

1. Switch MH to scepter and stack might.
2. Sit back or get a staff and use some AoE / build and man the siege.
3. Under cover of defensive siege, go and disrupt the enemy as much as possible, try to take out their siege or the people manning it. Be a total nuisance to the enemy team, use everything you have to not die and keep hitting them.
4. Don’t. If you can’t shake them however, run in the front to close the gap between the enemy and your team by disables and snares. But really, just don’t zerg unless you want to PvDoor, in which case refer to #2.
5. Disrupt them as much as possible, try to survive and get in and out of the group, having a small force chasing you weakens their main group. Same as 3 basically.