If you're not a music lover then it doesn't matter what speakers you put in.
You will be amazed at all the stuff that has to be pulled out in order to install the rear speakers. So it's a one-time opportunity to upgrade speakers, but only if you are a music lover. And then, if you get some decent speakers, you will be blown away at the difference they make, even with the OEM unit. I also used to think that Civic stock system sounds good but ever since I got some high end speakers in my other car, Civic X sounds absolute crap when previously it used to sound much better by comparison.
The volume will obviously feel low right now because I've noticed that even with fade in neutral setting, more sound seems to come from the rear speakers than fronts. As for speakers suggestion I'm hoping someone else can help you out if you're interested because I installed Hertz and Focal speakers in my other car, which are quite expensive.
