I like Nate, Oscar, Jett and Jonah of the suggestions above.
Not sure that these fit your criteria but what about:
Marlin
Murray
Ronan
Zander (or Xander)
Riley
Fergus

Out of interest, DS is Bosley, and everyone asks what it means and where it's from (it's old English and means 'grove of trees' but is usually a surname). I love that his name is unusual, but still easy to pronounce and spell - I think! We shorten it to Boz (the shortening part was important to DH and I too!).