Help me choose pls..
Mesmer is complicated. Ranger and Thief are relatively straightforward (Thief can become complicated once you start traiting).
Necro is strong AoE and can be amazing in sPvP and WvW, but so can Mesmer Thief and Ranger, it really depends on your playstyle.
Both Mesmer and Ranger are more overall in WvW (Mesmer can fit nearly any role and Ranger is relatively strong in WvW even with a recent nerf.)
As a Necro, you’ll probably want to join a small roam group or a zerg.
As a Thief, you’ll probably want to go solo or join a small roam group.