I enjoyed the first novella (Queen Song). I think it could've been easily expanded upon into a very engaging novel as I felt a lot of the character development and plot was rather rushed in this shortened form. 
 The second novella (Steel Scars) was pretty uninteresting to me and I skimmed the bulk of it. :/ 
 I didn't read the preview for Glass Sword, as I plan to read the actual book soon!