I love this sort of story. Good old space opera!
It's just a rollicking good read, with interesting character studies of 4 different sapient species (humans and three others).
I'm a little disappointed in the treatment of the main female character, who despite being "Queen of the Universe" (that's just a joke one of the other characters makes) still seems to require a husband to validate her existence, and the portrayal of humanity as the smartest and most adaptable of the four species is jingoistic, but that's pretty much in the nature of this subgenre.