re: How would you go about blacking out rear sights on a pistol?

Shouldn't be too hard to black out the existing rear sights (which have no significant utility since they're not night sights) and add a temporary white dot (paint pen, adhesive dot, etc.) to find out if you like that style.

I would personally lean toward a "typical" rear sight, with night sights (if you want them) that have no white outline. Once your eyes are trained to focus on the front sight and keep it in the "window" of the rear sight sight, you'll be GTG with any set of iron sights, on most any gun.

As my eyes get older I find a lot of utility in a narrow front sight and a "wide" rear sight window. This allows me to focus on the front sight and still keep it readily/clearly centered in the rear sight (when I need a carefully aimed shot).

The problem with any white features on a rear sight is that if you pick up a different gun, you may lose a second or two looking for the white feature -- and you may not have the luxury of losing that amount of time.

I think a bright front sight has merit and can't hurt. They help your eye focus on the front sight -- which is what you want.

Just my $.02 worth.