Totally agree. I spend several days to only get one level from 81 to 82. Its way to timeconsuming.
Thats not the only problem - running higher expeditions is way to risky/slower so it does not make sense.
But running lower expeditions only gets you low level items and only a very little amount of XP.

Reaching the max level should not be a question of spending weeks or even months.

Agreed. I stopped playing this because leveling was taking me way to long and became 1000% not enjoyable. Why should I spend 5 thousand hours to hit max level to have enjoyment.