Boutique Air in California flies PC-12 single-engine turboprops about the size of a Cessna Caravan (photo from [Wikipedia][1]). 

[![enter image description here][2]][2]

Their [baggage policy][3] currently is as follows: 

[![enter image description here][4]][4]

Note that two of the airports they serve do not allow luggage to be stored for a later flight so if they run out of space you might have an issue. 

Most people on these flights are not carrying huge piles of luggage. I carried on a fairly fat backpack with computer inside (four flight segments total) and had no issues (but was not allowed to put it in the aisle). Definitely a civilized alternative to the other option I had for LAX<->Oakland (Spirit Air). The only unfortunate thing is that you have to go through the same TSA nightmare as everyone else. 


  [1]: https://commons.wikimedia.org/wiki/File:BOUTIQUE_AIR_PC-12_N476SS.jpg
  [2]: https://i.sstatic.net/waB2Z.jpg
  [3]: https://www.boutiqueair.com/p/baggage
  [4]: https://i.sstatic.net/s5rUt.png