I don't like to really modify my glocks with aftermarket parts, however some of my gen 4s had such terrible triggers I had to start experimenting with some of them. I usually like a rolling break with a glock except for the slimline glocks for some reason.
I used gen 3 smooth face triggers in my two gen 4 19s and a gen 4 g26. I also installed the lonewolf safety plungers with reduce power springs and the 3.5# connectors (the ones that have a tapered body). That gives a really nice trigger to roll all the way through from the beginning of the trigger press. The oem 3.5# connector was also much better but has more of a abrupt wall than the lonewolf connector. My g26 had the worst factory trigger and somehow it has one of the slickest triggers out of those 3 glocks.
On the slimline I actually prefer the opposite kind of trigger. I was getting a lot of lateral hits at speed, like a straight line sideways on the targets. I finally sucked it up and ordered talon grips for the g42,43,48 and installed the Vickers flat faced trigger shoes and boy did that make a huge improvement so far! I also ordered more 8# connectors for the g42 and g48. I don't know if I got a magical unicorn g43 that came with the 8# connector or what but that is probably the best stock glock trigger feel out of all three. It definitely isn't a 8 pound trigger pull, I'd say maybe 7 pounds at the most, but a very clean break. I also ordered a ny1 trigger return spring for the slimline to test out, as well as some wolff 5# striker springs and reduce power safety plunger springs.
But so far I shoot the slimline differently than a standard glock. More of a prep to the wall quick then press through the wall.