Nine Hands
Explorer
I like it!
Do they get one At-Will Attack Power from each Class at Level One?
For Skills I think that you should Split the Skill Selection into Different Parts. Half of the Skill Selection from most of the Skill Options for each.
You can do the Half Option for Armor and Weapons as well. I would Favor Heavier Armors while Disfavoring Weapons.
When new Powers are Gained or Retrained does the Dual Class Character need to Split the Choices? Maybe there could be a Built-In Attribute Dependency so that only the Best of the Best for this Dual Class will be able to get far.
Balance will be Tricky. Combination of Powers from Different Classes is Very Complex. It could be Required to use up Three Feats from the Heroic Tier and to not allow the Dual Class to take a Paragon Path, instead the Dual Classed Character would get a Heroic Tier Feat at Level 11, 16, and 20.
Yes, you would get a single At-Will from each class, because you must maintain some sort of balance between the two classes powers.
My suggestion with this system is to split powers between classes, although if I were running a game, I wouldn't force this on anyone unless necessary. Most of my players are role players and butt kickers. Power gaming is not their thing.
I deliberately avoided adding too many areas for choices, 4E seems to hard code lots of class abilities at first. I'm sure we will see alternate builds and class paths in next few years.
When I designed this, I followed similar rules to how 1st Edition D&D did its multiclassing. You started with two or three classes and split your experience between them. Now, in 4E, that isn't necessary anymore as we have a unified progression for all classes.
I could easily see a variant of this using the best armor proficiencies and the worse weapon proficiencies, that would be easy to do. As for skills, that sounds like more work than I want to put into it, but feel free to do it
