I will reserve my vote for now, because I've not played the game and I've no feel of how XP works in ESO. However, in my opinion, good amount of XP is when you don't run out of quests to do to progress your level and are forced to grind random mobs. That is the biggest game-killer for me. As long as there are quests, preferably story lines progressing me from level to level smoothly, it's a good design for me.
At the same time, I don't want to be zipping through levels at a ridiculous speed. I'm one of those people who prefers leveling to End-Game. End game is literally the end of game for me. Raids bore me after the first one-two runs through them, PvP is very situational and requires me to be in a particular mood, and dailies ... there's nothing I hate more than dailies in MMOs. So really, I am more for a slow, long leveling process, as long as it leads me through interesting story arcs and I do not need to fill in the gaps with mindless endless grinding.
I think leveling through Crafting as an alternative to normal questing is an interesting idea that I'd like to try. But as long as it also does not entirely replace the normal ways of leveling.
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