I would certainly have no problem with a GM wanting to house-rule something like this:
- The barbarian can choose a weapon type (broadsword, axe, crossbow, etc.) and get +1 AD with that type.
- The barbarian attacks as normal with NO weapon, using 1 AD with his fists (because of size and strength).
This might even things out just a touch in the long run. Granted, the dwarf might not stack up for BP when
decked out with every artifact available - but not one character is going to hold ALL artifacts. And, to be
honest, I would vote against the dwarf being able to use the Spirit Blade - it would just be too long and
hard to wield well for the dwarf. (yes, I know...I said long and hard...

)
This is why some minor role playing can come into play to make things more interesting. Dwarves have
a natural hatred for goblins, and vice versa - so, any goblin will immediately attack dwarves, and the
dwarf should go for goblins whenever possible. Maybe add in a rage factor for the barbarian, perhaps
if he drops to 1 or 2 BP, or if he loses more than 2 BP with a single attack...something like that.
Maybe come up with some dwarf-only artifacts to toss into the game. Allow the dwarf to reset
a trap differently, then it can hit monsters. Of course, to do that, the GM would have to play fair
and either have a stupid monster hit it at some point, or require a search roll to find the trap or to
notice that the trap has been changed.
Add in a language factor - the barbarian and dwarf might both know the Common Tongue. The barbarian
would know his own tongue, and the dwarf would know his, and make use of it somewhere with a puzzle.
If you're playing Kellar's Keep - maybe the dwarf is the only one who can guide the heroes through...he has
to find the right markers to find the next door, and only he can read the stone map that must be found.
There are lots of ways to make each hero stand out...and a GM should utilize as many as possible, as many
as can be thought up and implemented...they don't have to change the rules a lot, but they allow each hero
to shine at some moment or another, and the players will be all the happier for it when it is their turn.