Magatamas, Battle Armor, Refinements.

I've found Battle armor to be the fastest until you hit your Rank 3 wall.

For whatever reason I spaced on everything else but yes literally it's everything.

For your group skills I'd say however level them until you feel it starts getting out of hand usually its around L60-65... and dump all that money into donating to your group(Should be doing this daily, dump your max donation. Group skills are more reward able that strengthening.)

Because hitting 3 is easy I'm implying after 3 it begins to drag on a bit longer.