HoH is really the only option for 60-61 if you want to do solo leveling and not use the DF. At this point, you can use the Duty Support function to level through all the HW content, but they have not added the dungeons yet for Storm Blood. HoH can be soloed and then spammed. Once your weapon and armor is pretty high, it is maybe like 15 minutes or so to blow through the levels with a tank, a little bit more if doing it as a healer and you can do it quickly if DPS and are careful.

Once you hit 71 though, you will then switch to Bozja until 81ish... then i switch to duty support, fates and more Bozja. The Leveling and MSQ Roulettes along with the End Walker tribes also provide a ton of EXP daily. took only a few days a couple hours per day leveling an alt job to get from 81 to 90.

I am finding the worst of the grind to be 61-70