Runes of Magic US / AU

You should have been level 62 at the start of LOM, not at the end of it. It's possible to level 2 classes together when going up the main quest line, but doing three is going to cause issues like this. You should be 64 or 65 going into Redhill which is why quests aren't showing for you.

Solution: Daily grind a side so you can unlock more quests. Once done, stick with that class through the main line till level 98.
Save all side quests for your secondary/tertiary.

Do main questline on main class, side quests for 2ndclass, dailies on 3rd class. This will keep both primary and secondary classes close in levels but still allows you to level up the 3rd level.

Keeping in mind that in some cases, letting your main questline get too far away from your side quests can cause permanent damage to your Morrock line... proceed with caution.

Well, I wouldn't agree entirely with Heron, but you really do need to be careful with that Morrok line. Sometimes it will jump across the map without warning and you can lose it easily. (There's one zone that the entire quest line stops unexpectedly and then continues after some side-quests are completed. If you completed the side-quests before the Morrok line reaches that point, the Morrok line doesn't want to re-appear. This may be what Heron refers to...?)

My preferred tactic is to pay close attention to the level of the quest and use dailies to make sure I am that level. It's slow going, but it has worked for me. I use the main quest line to level my main preferred class and the side-quests to level another. I always try to keep that second class within 10 levels of the main class - after all, you really don't need a third class.
But, my third class gets largely ignored and it's just there for any time I get 'bored' with the main classes.

Almost everyone can offer advice on how to level, but one thing for sure, there's just enough quests to level your main class comfortably, a few left over for a second (and then dailies), but there's nowhere near enough to level to level three classes at once.

You're going to have to make a choice...

Darn it! I was going to disagree with Heron too, but Yrcanos already did; and burd is right for a change.

OP, a zone has anywhere from 100% to 120% XP for one class. You can level 1 easily, 2 with a lot of dailies. 3 needs frequent purchases of daily reset tickets during bonus XP weekends or playing for years.

Look up ToSH plvling.

BUT

only do it by yourself with no help from anyone else. your mage side should be handle 1 or 2 bugs.

WARNING

It's considered an exploit if anyone else plvl you at your level and can result in a ban for both players. But if you do it using only your toon, it's completely legitmate as you are only grinding xp/tp for yourself without using any exploits.

You can turn in quests 10 levels below the quest, use this to your advantage by maintaining a 10 level difference between your main class and your secondary. Works really well with dailies. Or, just run your main class to cap using only the mainline quests, then come back and do the side quests on your secondary. Tertiary classes will always be an issue, but best to pick one to slide and get it done later, may want to save some quests to turn in on bonus exp weeks.

I've lost count of the times we've had to bail out someone's morrock line in Sarlo. There's at least two places it routinely breaks, and always when the player let the mainquests get unbalanced from the side quests. Yrcanos know this as well as I do, I have no doubt. There's also the omega platform in chrysalia and I think Weeping Ignacia that also glitch.

And that's just the ones fresh in my mind that are in your future. Theres places it can break in early Zandorya that you seem to have cleared already.

Remember, folks, the same developers who bring you our thoroughly vetted content releases also make our gm tools. While we can and DO fix broken questlines, there have been cases where a questline stayed a bit buggy forever after, needing still more interventions from support. For this reason we are careful to require that players complete their own questing as much as possible, instead of magic wanding the harder ones away on a whim.

I mean it. Proceed with caution.

The bugs that are spawned give a very large amount of Exp, yet are harder to kill, so you kite them as a champ, or more, or S/M. It's no fun to do, but much faster than questing if you are capable of doing it the legitimate way.