The way it should work is that you receive battlequests straight from the aetheryte camp rather than having to go back and forth between the camp & the closest city. It'd be a great quality of life change because even they add hundreds of new quests to do, there's still going to be a time and a place for the levelquests when you're leveling different classes.

As for the limit, I'd change it a flat amount per day that resets at a specific time of the day. Say, noon server time. Then give a fairly large amount of quests per day -- say around 20 or 25. That's more than enough for most players.