Half-elves are already a thing and I'd like to see more dwarven love on the server, but the kinda potato appearance of the vanilla dwarves is probably something holding them back. I don't think I'm alone in thinking that dwarven lore is pretty awesome, but they should have the same options as elf-blooded characters to attract more players.
In my suggested implementation they would use the shield-dwarf abilities (since they are the most common type of dwarf). From what I've read half-dwarves have the same physical abilities as their dwarven parent (+2 Con bonus, darkvision, etc). Of course making a half-way-between spread of abilities similar to how BGtSCC has implemented half-elves might be better for more variety, but would take longer to design, test, and put into the game.
I'd suggest that they have the physical appearance of (slightly shorter) humans, or perhaps even half-elves. A combination of both human AND half-elf heads might actually be more appropriate after reading below, depending on their parentage:
http://forgottenrealms.wikia.com/wiki/Half-dwarf
Half-dwarves
Half-dwarves (also known as dwelves or halfbloods) were humanoids born through the union of a dwarf and another humanoid race.
Ecology
Half-dwarves were usually the result of a dwarf mating with a human, gnome, elf, or halfling. The offspring of a dwarf and an elf was known as a "dwelf" (which was pluralized to "dwelves").
The fertility and offspring of half-dwarves was similar to that of half-elves. If a half-dwarf mated with a pureblood dwarf, the offspring would be a pureblood dwarf. If a half-dwarf mated with another half-dwarf or a nondwarf, the offspring would be a half-dwarf.
Physical characteristics
Although slightly taller, half-dwarves were not a distinct race. Biologically, half-dwarves were almost indistinguishable from dwarves.
The physical and mental characteristics that were inherited by dwelves varied between individuals. This meant that some dwelves had more elvish characteristics and some had more dwarven characteristics.
Culture
Like half-elves, dwelves would adopt the cultures and gods of whoever raised them.
Non-dwarven mates who entered into dwarven culture were honored and respected by dwarves for their bravery and loyalty.
