@OP
I agree with you on the ability to see tunnels and hidden buried things. Its kind of a dwarf thing.

In terms of blacksmithing maybe don't start with any points but gain points in them more rapidly. ie every one skill point invested is the equivalent of two skill points. A dwarven skill you get just for being a dwarf.

I think that in terms of charisma dwarfs should have a bonus against being charmed. If you try to flatter a dwarf the dwarf will see right through you more often than not. After all he knows he's no elf.

I would also give them a bonus to inventiveness. That is the ability to understand machines and other contraptions. Dwarfs have to be inventive to make up for there short-comings bah-dum-tah-tish!