Few questions for a new player

[Enkidoh]

1. Increasing a leve's difficulty gives a small exp and gil bonus after completion (when you turn it in at the levemete for your reward), but it also increases the level of the enemies you have to fight (I'm not sure how crafting and gathering leves would be affected though). I normally don't set it any higher than a level below me as I find it's just to difficult otherwise when undertaking a leve solo.

2. The levemete at each city's Adventurer's Guild is kind of like a central kiosk for all the levemetes in that region (for instance, the one at Gridania deals with leves for all areas in the Black Shroud), where as the individual levemetes in each area deal only with leves for the area they're in (for instance, Tierney at Camp Bentbranch only dispenses level 10-15 leves for Bentbranch). It's up to you whether you grab a leve from the Guild or just head out to the camp's levemete and get it then.

3. Rested exp only decreases when you gain exp from defeating monsters - exp gained through other means, like a FATE completion reward, completing a levequest, completing a sidequest or some other means will extend the rested exp bonus further (the exp bar will turn blue if the bonus exp exceeds your current level). And it should go without saying your rested exp will increase whenever you're in a 'sanctuary' (denoted by the crescent moon icon under the exp bar) - like a camp with an aetheryte or inside an inn room).

Hopefully this hasn't been too confusing for you.