Playing Pathfinder and D&D for quite a while now with only one PC and one GMPC (gestalt characters), we encountered a problem with the core XP-tables. The fast and normal tables are too fast overall and the slow progression is hard for early levels regarding our playstyle. So I created a custom table thats quite fast at early levels and gets very steep at higher levels. The idea behind that is the decreased efficiency of killing stuff. What was quite new and adventurous at first becomes more routined and grants proportionally less experience to advance a level. That leaves more room for quest- and non-combat-XP. In addition, a unique or very special enemy might be worth a lot of bonus XP for being a greater experience.
So here's the custom table:
2nd 1.600 XP
3rd 4.000 XP
4th 8.800 XP
5th 18.400 XP
6th 34.400 XP
7th 63.200 XP
8th 108.000 XP
9th 184.800 XP
10th 300.000 XP
11th 492.000 XP
12th 773.600 XP
13th 1.234.400 XP
14th 1.900.000 XP
15th 2.975.200 XP
16th 4.511.200 XP
17th 6.968.800 XP
18th 10.450.400 XP
19th 15.980.000 XP
20th 23.762.400 XP
The math behind: to advance to the next level you need an amount of XP equal to twice your current level times the XP for one monster of a CR of your level: lvlX to lvlY = 2*X*CR(X). Only exception is level 1 to level 2.
So to advance from level 19 to level 20, you would have to kill 38 ancient red dragons for example. Better to find some more rewarding experiences.
Opinions/critiques welcome.
We play gestalt cause we only have two chars to fill the roles. I think for a party of four PCs you could halve the whole table. The level progression would be fast till level 5, medium till about 8 and slow till 10. After that it's even slower than core slow.
Apart from that, the treasure per encounter table should be updated for the custom table, maybe I'll look into that sometimes.