I decided to have the normal level progression liniaer cause in most cases the amount of XP you will get from things wont increase. So in order to unlock some of the perks you should be able to level relativly fast.
The skills do require more XP each level, so getting to level 3 for a skill should be fairly simple.
The skills do require more XP each level, so getting to level 3 for a skill should be fairly simple.