Other than the cut out magazine, window grips and fiber optic sight, what other mods were made to this,
The ASP was quite a ground breaking in it's design features...many that are now considered very common...however, it never had a fiber optic sight.
1. Hooked triggerguard. Although it's usefulness is questionable, at the time it became very popular.
2. Lightened slide. While there had been cut down 1911s prior to the ASP, the lightening cuts in the slide were a new design.
3. Beveled exterior. Not even a custom consideration back then.
4. Black Teflon coating. This was the first use of this on a gun that I remember.
5. Removed hammer spur for snagless draw. No one did this back then.
6. All checking removed. The gun was designed to
slip into the correct firing grip from recoil, if it wasn't attained o the draw.
7. Magazine finger rest slanting the correct direction to fit finger length
8. Magnetic retention of the magazines in the magazine carrier
and did they ever base a similar model off the double stack 59 series?
ASP never did. But Devel did make one, along with their version of the M39. These were the basis of the S&W M469