I have had good luck with various red dot/reflex style sights on handguns. There are tons of variants available and most are reasonably priced also. I have a Taurus Raging Bull on order myself, and plan to stick with iron sights for as long as I can, but will probably end up going with a 'dot' type sight at some point. I don't know of any aftermarket replacement sights for the RB, but I do know that there are some sight paints out there that make standard, black-colored irons more visible....perhaps those would be worth a look
As for 'dot' sights, my current favorite is Bushnell's Holosight; even on a rifle, it is fast, easy to pick up, and fairly accurate for a non-magnified sight...I only wish they made it with a green reticule
That said, there are many equally worthy (and less expensive) alternatives out there. It all depends on what you what. There are numerous options, so hopefully you'll find one that works well for you
Kind Regards,
.450 Marlin
P.S. I have never liked traditional scopes on handguns...but I haven't shot with them much either.