Mod requests (orders).

Here is something similar, but this mod doesn't increase the number of levels; instead, it reduces the amount of experience required to reach that level (starting from level 25). I haven't tested it myself.

Level 26 requires 220,821 experience.
Level 30 requires 396,675 experience.
Level 40 requires 3,140,344 experience instead of 1,215,939,194 as in the original game.