The repeatable leve quests are the best xp/allowance expenditure even though you have to craft a lot more. If you can hand in all HQs you can get 80-100% of a level per allowance that way.
A little easier and the single hand-in leves that send you elsewhere to complete them, it's not as much as the repeatables but sometimes they are easier items to HQ or craft on the newer servers where the mats needed might not be as plentiful.

For you, there's a lvl 35 repeatable in Gridania with 3x Walnut Macuahuimehs. I've been compiling the repeatable ones I've found so far which doesn't go up super high since I started at launch.
http://bit.ly/14I2bOc