Rested will get you to about level 10, Leves will work to an extent but I dunno... You'll probably get bored real quick with leves, Food is ok for sure +x% exp, and the FC buff is of course going to help the whole way through.
Recommendations: The Friend hat that gives +10% or what have you till level 25, or the moggle/helm of light for +10% till level 10 at least.
Honestly I don't see the point in rushing to 50 unless you're gunning for a Shiva weapon OR doing FCoB ASAP... otherwise you're getting your Tome gear just as fast as everyone else, and can grab a UAT weapon more or less out the gates.
As mentioned by Stormrider, the new bonuses for "class in need" will go up... so all you tanks and heals, get ready to make a mint
