There are 5 ways to level in this game

1) Solo Grind.. very slow and very low SP.
2) Leves.. Repeatable quest (sorta like fields of valor) designed now for solo game play... these also give fairly low sp but give rewards as well.
3) Quest and Mainstory... Quest are fairly low sp, but they now give sp. Defiantly not a quest based game though you cannot souly level on quest. Mainstory line is massive sp.. with the upper ones giving 40k+ sp. But again not enough of these to level up on alone.
4) Dungeons.. SP is decent, a ton higher then the other 3 previous options.
5) Party Grinding... what you did in XI. The top sp in the game bar none atm able to get between 20-35k sp/hr depending on camp and party composition.

For someone reason everyone is still focused on 1-2-3 for leveling so unless you have a static or ls you will suffer. It will be like this until people change their play style.