do i get a higher challenge rating if i make an all ecl race party with the same level loss like an all drow and duergar party? - if so, then i wouldn't be behind in levels because i get more exp.
You would get much harder encounters. Although I think that you would get stompted if you had all ECL chars in the beginging. Imagine a party of level 1 or 2 chars fighting a level 4 encounter. IMO even with the racial benifits the large battle that you see close to the begining of the game would be very hard.
the point is, i am not too long behind in levels (compared to non ecl chars) because i get a higher challenge rating (all chars have the same level in a duergar/drow only party) -> more exp. or am i wrong here?