Re: glock slide release
First the slide release on the Glock was designed for inspection mode only. The Glock was designed for you to just pull back on the slide and release during a mag change. Being left handed I had been doing that forever, so it came natural to me.
My old Dept put extended slide releases on their issue Glocks. Those use to doing it the old way like them. They are not hard to change, nor are they expensive. Most sites that deal in Glock parts sell them.
Guns are like Jello, there is always room for more!