Samurai
Adventurer
Here is the list of changes and additions I currently plan to use. It includes fixes for every problem I could find, such as the Skill Challenges and multiclassing. It adds quite a few new feats, including the return of some old favorites like the Paladin's Mount and a Ranger's Wild Empathy, it has simple rules for the Sorcerer (a variant kind of Wizard/Warlock), rebalances some powers and abilities, and in general significantly improves 4e in my opinion. Many of the problems were identified by my fellow Enworld posters, as well as some of the fixes. I hope you find this useful, and I'm happy to answer questions!