If I comprehend this right. Ecl means that he system considers a character a level or two higher than what he actually is. Example, Fehriel has a ECL2 from his subrace. Which means the system considers him a level 8 instead of his current level 6. So basically to reach level 7 I would need to get the amount of xp to go to level 9 and theoratically hitting the "wall" sooner than the other players.
Would that also mean that to reach level 19 I would have get the xp of someone reaching level 21, which mean the 3 million xp?