I must have variety, and be able to get the "full experience" of ESO.
I'll give you all that insight:
1) AD Khajiit Nightblade - Stamina DPS - base game story arc, theorycrafting,
2) DC Orsimer Dragonknight - Tank - Orsinium, and DC only for skill pts for crafting,
3) EP Argonian Templar - Magicka Support - EP and Morrowind, dungeons,
4) AD Altmer Sorcerer - Magicka DPS - Vampire, eventually an evil playthrough of AD and Summerset,
5) EP Bosmer Warden - Stamina DPS - Berserker Werewolf via player bite, TG, sequel story arc,
6) DC Breton Warden - Hybrid DPS ("the anti-meta") - DB, evil playthrough of DC, eventually PvP
7) AD Redguard Templar - Stamina DPS/maybe Tank - Summerset to AD, eventually Pack Leader Werewolf via spawns