Okay. So I'm going to suggest some ideas that are my personal opinion, so they don't mean to be perfect and they even might have flaws.
1: What about starting at lvl 50 cap, and gradually rising cap by five every 3 or 4 months so we can get a chance for achievements, sets and really enjoy the game, so it doesn't feel that you have to rush for cap. This would be good for casual players too who don't spend 12 or more hours a day online.
2: The exp rates should be low, because I don't see the point in reaching cap in 10 hours. It doesn't give longevity to the game. Now, when talking about drop rates, like trophies, cc equipment fo bosses and armor or enchantment chest should be higher. nobody wants to kill a boos 150 times to get a trophy, or kill 150 elites to get to armor boxes and then dont get what you were looking for.
3: World bosses should spam a little quicker.
4: Crystal altar rotation should be once a week, so more people would be able to get whats on it before changing again.
5: Honor Stars. I don't think POD is game breaking for classic. But if you are going to remove it, maybe put some other way to get the honor stars.
Remember, before you jump all over me this is just my personal opinion. so tank you for reading. If I think about something else, I'll post it.