Maintenance for the week of December 22:
• [COMPLETE] NA megaservers for maintenance – December 22, 4:00AM EST (9:00 UTC) - 8:00AM EST (13:00 UTC)
• [COMPLETE] EU megaservers for maintenance – December 22, 4:00AM EST (9:00 UTC) - 8:00AM EST (13:00 UTC)
Werewolf definitely, even if you don't end up using the skill line there is a 15% bonus to in combat stamina regen which would undoubtedly benefit your character. The skill line is also rather good, and if anything it can add some enjoyment to the game if you don't use it practically for dps. In my opinion vampire is much more beneficial to a magicka based play style.. though I wouldn't recommend it for end-game with it's large fire damage debuff.
Werewolf is always better for stamina builds than vampire, namely because without even slotting or using any werewolf abilities you still get 15% extra stamina recovery with no downsides or penalties whatsoever (you only take the extra poison damage while in werewolf form). Werewolf scales off of max stamina and weapon damage as well.
Vampire abilities all use magicka, and scale off of magicka, which makes them more suited to caster builds. You also always have the penalty of taking more fire damage and regenerating less health, and it makes your character ugly as hell to boot.