Any specific years/generation? The Prius gets better mileage, but some people may prefer the "normal" looks of the Civic.
I wouldn't go that far. Trunk space is a bit reduced, but not horrible. It's the IMA drive I couldn't deal with. Every time lifting off brake pedal, gas engine comes on, yuck. Civic Hybrid is painfully slow 0 to 60, but word is it has a bit snappier steering and handling FWIW.
... the other thing is, unlike Prius, you can purchase the non-hybrid version. Last time I checked there is significant price differnce.