Racial Paragon Classes are detailed in Unearthed Arcana. These extremely short classes offer a way to expand your racial abilities and make your character feel more "elf-like" or more "dwarf-like". I really like the idea behind the classes and I'm toying with the idea of using them in my next game.
My thought would be that the players would start the game as the racial paragon class and, when they leveled up, they would either choose to continue in the paragon class, or select a new class. (Sort of like starting as a common person, then leveling into a standard class.)
Ability-wise, how do racial paragon classes (RPC) stack up to the actual classes? I'd assume that a party of 1st level RPC characters is going to be weaker (due to lack of specialization) than a normal 1st level party, but I'm not sure how much. Is it possible to say something like "A 2nd level Racial Paragon Class character is roughly equivalent to a 'real' 1st level character?" Could they handle the same encounters a 'regular' party could?
(Let's just consider the RPCs for LA +0 races; I'm sure that the Drow and Half-Dragon RPCs would throw things off.)