Best is a hard term to use, but IMO Humans do give the most benfit. Free expertise with Swords / Mace, baked in PvP trinket AND free rep all sound pretty good.
Dwarves do have the extra expertise on Maces, but frost resist is so so, and gun spec is not used at all. Find treasure is only marignally useful as well. Stoneskin is useful, but only in certain situations.
Squidfaces are nice, but mainly for the extra hit %. It's your call really. I rolled human after looking em all over, but all are pretty decent.