I decided that I wanted to go caseless this time around. I'm careful with my iPhone and didn't want to mask the sleekness of the Space Grey model.
I went into a Zagg outlet and they installed InvisiShield for the back and sides only as per my request. It looks great. The parts that aren't covered are the bottom (due to all the components there), and the buttons. This only cost me $20.
For the front, I ordered an SGP Ultra Crystal screen protector and managed to install it by myself on the first try perfectly aligned, without any bubbles, dust, or fingerprints underneath.

It has 0 orange peel effect, and the rainbow effect seems less noticeable (if any) than the PS Crystal I got for my 4S last year. This ran me $14.
Zagg's and SGP's films are compatible with the entire iPhone 5 series. For $34, I got as much protection as I can get without getting a decent fully-fledged case.
It's a great combination. It's a bit odd because the whole phone feels smooth and grippy, whereas my 4S's case (and my mom's 5s without a rear film) had some texture to it that felt good on my hands, but it's a minor adjustment.
The main thing I worry about is the scuffing I have heard about on the chamfers. Those are left uncovered even with everything I still have. I have heard that the Space Grey color is more resilient than last year's Slate, so I guess I will just have to be careful and let whatever happen happen.
Apologies for the weirdly-lit iPad photos. Not sure why the thumbnails have the orientation of the pictures looking all wonky, but if you click them, they load fine.