What sights do you prefer on a subcompact CCW?

I purchased a Walther PPS M2 to be my CCW (before the rebate was available unfortunately) and have been practicing with it at 28 feet. I cannot seem to get consistent patterns with this thing and thus don't feel comfortable carrying it yet. I have the factory (non LE) sights and the thing I think may be contributing to my struggles is the gap in the notch of the rear sight seams overly large making vertical alignment difficult especially for a pistol with such a short distance between sights - way too much room for misalignment, IMO. I find myself struggling to line up the three dots while keeping the front sight centered between the rears and on target. I think I'd prefer a tighter sight picture. I know it's not all about sights but even when I'm at my very best fundamentally (grip, trigger pull, etc..) my eyes still struggle with the sight picture and I find myself bouncing the front sight back and forth unable to find the center point before pulling the trigger.Anyone have any suggestions on sights with a tight sight picture?EDIT: added example of sight picture via /r/CCW http://ift.tt/2yKh1EZ