Balancing 4+ multiclass

Any other server allowed 4+ multiclasses?

What balance changes did you make and what do you still see as a problem?

Currently the biggest problem I see with 4th multiclass is that it removes a choice from melee builds. Everyone is now RDD+WM and there isn’t anything else that could compare (excluding custom prestiges).

I am looking for some suggestions how to balance this out. Any takers?