I have an alt acct farmer. I can farm a new toon to 30 in half an hour? With coffee break part way through.
I was making a ton of toons last year for about three months. Leveling 2-5 50s a week. Most of them I did NOT farm. Or farmed for 10 minutes to get to 15-18. My preference for levelling is 4 DFBs (for the boosts). This puts you at 16? With 2xp. Forget the exact number. Then all the TFs, SFs, and Trials in order. (That order determined by last level of the content, not first). So, a 20-40 is run at 40 or later.
To me this is by far the funnest way to team and level and learn a new archetype/powerset/build.