EverQuest has always resisted creating any "solo-path" for levelling through the game despite it being difficult to get from 70 to max on a live server without being carried by higher level players. You can probably Molo as far as 70 on all classes with a bit of determination but after that it gets pretty rough. I think they've done that so the game stays "on brand" I think and keeps it different to the mainstream MMO, largely as the history of the game was always as the less-easy MMO's and it's core audience were players who preferred a challenge. If they cannot or will not create any solo-levelling path then I think they should look at creating a side-kicking system so that no matter what level you are you can play with people at max level to get XP. A solo-levelling path would be more familiar to players who are not formerly EverQuest players and would open up the game to a much broader audience, it could have lower quality rewards than found in group missions as the main focus of doing the solo path is just gaining levels, so long as you can obtain very basic level-appropriate gear that lets you tackle that solo path it would do. I don't think it would even need to take you all the way to max, within 5 levels of that would be plenty. The side-kicking system would be something that's been used in a few other MMO, and would retain the "must group to get anywhere" ethos but make getting into a group in the first place less of a nightmare for under-levelled players. Overseer at L85 is certainly a useful way to gain additional XP on a character but that's a mostly passive system, you aren't actively playing EQ once you have sent your agents off to their missions.