Shield Dwarfs get medium armor proficiency. Humans get light armor proficiency, shield proficiency, polearm proficiency, +25% carry weight, and an additional skill. Half Elves get light armor proficiency, shield proficiency, and polearm proficiency.
Which means that for a caster class, those free armor proficiencies could become rather enticing. Of course, they're of no help whatsoever if you're looking to do a martial character because it won't stack in any way with class bonuses. A Shield Dwarf fighter is objectively worse than a Hill Dwarf fighter. A Wood Elf fighter is objectively superior to a Wood Half-Elf fighter,
though so does gith give medium armor and proficency in things like greatsword... there is better options then shield dwarf in game if your just looking for armor upgrade for a caster.
