http://www.project1999.com/forums/sh...15&postcount=9
I searched Velious Experience Penalty.
That thread is named "Hybrids, What Happens". The post I linked is a quote of the developers notes on what happens with exp penalty and their logic behind the changes. It's a good read.
Beyond your main question, I don't know how to answer your other questions. Eventually Rangers get Offensive and Defensive skill cap increases, 1-2 months in they get several spells added (Skin like Nature, Fear Animal, etc.). Level 55/60 Rangers gain Trueshot/Weaponshield disciplines day one, which increase bow damage for 2 or 3 min or make you parry every attack for 24? Seconds (respectively). I forget exact times on the discs, the wiki knows them better.