Why worry about how fast it gets there. A few days here and there don't make a big difference does it? To me, questing always made the most sense as it gives the toon a history and accomplishments. Thus making it look human like. Also, run your professions and auxiliary professions like fishing, cooking and the like to look like a person who actually plays. Achievements are also good. Takes a bit longer but my dad always told me anything worth doing is worth doing right.0
RAF levels like nobody's business. I used to enter dungeons and gain at least 1 level if not 2. RAF leveling can be done but the toons quickly move to the next area. And if you try and level them together they will drift apart quicker making it harder to level together. I used to do a lot of multi-boxing and saw this quite often.
So vary the leveling with a few dungeons and some battleground, you know just like you would normally. Of course, there are plenty of styles of play. I liked the achievements like loremaster or explorer and the like. Where my son liked PVP and dungeon and raids.