I don't find IWB uncomfortable, but YMMV. It's hands-down the easiest way to conceal IMO.
Personally, I don't care for cross-draw. I find it slower and when presenting the weapon there seems to be an issue of covering non-targets with the muzzle.
I have three holsters for my Glock 23 that I use regularly. An IWB from Blade-Tech, A OWB from Sidearmor (both kydex) and a leather Talon Plus IWB from Lou Alessi.
The Sidearmor OWB has slots for the belt and is a fine holster, but after lengthy wear it does tend to drag the belt down.
The Blade-Tech IWB attaches to the belt via straps with snaps. It's very secure, but at least with mine, the snaps are a bear to snap/unsnap. I leave it snapped. This holster is also available with J-hooks instead of straps.
The Alessi uses a stout plastic clip that fits over the pants (under the belt). It's hard to describe, but the 'Talon' portion of the clip secures the material of the pants to the holster in such a way that you'd lose your pants before losing the holster! At the same time, it's easy on/easy off.
If you're like many of us you'll end up with several holsters that have been relegated to the sock drawer