IIRC there are add on rails made by someone which attatch somehow or another, i suppose ya gotta do some drilling.
IIRC ya can change some of the springs (the mainspring?) and that will help some and still be reliable, mostly helps the DA pull though.
a good trigger on a 92 is possible, my neighbor has a berretta version and he's done a trigger job on it (well he didnt do it but a 'smith did, dont remember the name but he works mostly on 92's) and its pretty good in both modes, to be honest as good as any DA/SA i have seen or handled.
and dont get me wrong, imho both the taurus and the berretta are great pistols, but imho there are a lot of better choices for an edc pistol around they are just too big, std or compact versions, heck imho its easier to carry a full size 1911 vs a 92 because the 1911 isnt as bulky.