Agree w/ GeoffR on C.J. Cherryh's Alliance-Union books and jehane on Harrison's Stainless Steel Rat.
Timothy Zahn's _Ikarus Hunt_ is also quite good.
If you like Star Wars, then the Han Solo Trilogy by Brian Daley is quite good, and the Lando Calrissian Trilogy by L. Neil Smith also.
Chris Claremont's First Flight books start off a bit rough, but the last is decent enough to leave one regretting that there aren't more.
Some books in H. Beam Piper's Terro-Human future books (available in an omnibus here:
https://www.mobileread.com/forums/showthread.php?t=47980 ) touch on piracy, notably _Space Viking_.