I haven't worked on gen4's but I have done a lot of work on gen3's. The trigger I like best for my carry Glocks is this;
o Smooth faced trigger from a full sized gun.
o Glock 3.5 connector (part #00135) from glockparts.com.
o Six pound trigger spring from glockparts.com.
o A full 25-cent trigger job, which is polishing of all of the contact components with a Dremel, polishing cream, and a polishing wheel.
These mods result in a measured trigger pull of between 4 pounds 12-14 ounces and 5 pounds and will be smooth with a crisp let off and excellent reset.