Here's what I've been doing that I've had really good results from (this was my first one that I made for myself, They are a bit more refined now). The leather and kydex are riveted together, and I also use hooks that are attached at the bottom then the belt runs on top of the clip (j hook design) so you can tuck a shirt in and the only thing visible on this design is the small tab at the bottom that grabs the belt to prevent it from being pulled out. Also on most holsters I make a couple holes that the clips can attach with column type screws so the height and cant can be adjusted. I've carried this one countless hours for the past year or two and it is super comfy and just kind of disappears in the waste band. It allows the gun to have that "click in" kydex operation but has the comfort of leather against you instead of kydex.
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As far as a liner for a holster I think in most cases people who use a gun as a EDC realize that the gun is going to get worn if you carry it, I know this was a little tough for me when I bought my Kimber, I hated the thought of marring it (as well did my wallet). But I figured I bought the thing to protect myself and use, not to sit on a shelf and look pristine.
But if I were to go about lining a holster I would make sure there is some kind of mechanical attachment. I would think sewing it along the edges would be a good route to go, but use a heavy duty thread that you would use for knife sheaths or something would work. Maybe a good contact adhesive as well to keep the whole of it where it should be