As far as I know most are probably going to leave a few mm's of the screen uncovered, they maybe ones out there that do cover the whole front of the screen, maybe someone else will come along and suggest something.
To be honest with you though, it should be fine with that case and screen protector though, I mean I used my old iPhone 5S and iPhone 6 with no screen protection what so ever, I keep it in my pocket all day at work and when I sold them I couldn't see a single mark on the screens. I do take care though, like only putting my phone in my right pocket with nothing else in there but the phone, then keys/change in left pocket, worked for me. But when I got my nice shiney new 6S I wanted to cover the screen so just got a cheap plastic one and its doing the job.
If your paranoid or abit clumsy then maybe it's worth finding a bigger screen protector, but otherwise I'd be very surprised if you managed to put a scratch on the few mm edges that's not covered.