Many here advocate the affordably priced Larue MBT2 4.5 lb two stage trigger.
I like the incredibly smooth, crisp Geissele SSA-E, which is a 3.5 lb total pull through.
Two stage triggers act like a single stage with a long pull.
But, if you press slowly, you feel a "wall" at the end of the first stage (about 2.3 lbs with the SSA-E). You can hold there, practically indefinitely while adjusting sight picture, breathing, and then apply just a little more pressure (an extra 1 to 1.2 lbs with the SSA-E) and the hammer falls.
But, if you just want a lighter single stage trigger, Timney makes good stuff. Caveat: Timney triggers, like many others, are self-contained cartridge drop in triggers. Because they do not have the exposed spring "legs" to capture the detents or grooves in the two pins that hold the trigger groups in place, those pins are not secured and can walk out. You might need to use special anti-walk pins.
Mil-spec type trigger groups (including Larue and Geissele) have separate parts. The spring legs will capture the standard pins and hold them in place. Just a thought. These triggers retain full power hammer strike for reliability.
Some might come along and recommend JP Enterprises "yellow" trigger springs". They cost only about $10. They reduce trigger pull to about 4 to 4.5 lbs. however, they reduce hammer strike force and might not be a good choice for home defense or other situations where 100% reliability is essential. They can be a viable choice for purely range/recreational use.