In the end, three factors finally caused a groundbreaking shift in phaser technology that has gradually made its way into firearms utilized by all the major Alpha Quadrant species. These were, in rough order of priority:

1) The first true industrial replicators came online, greatly reducing the difficulty of procurement and logistics and reducing the cost to near-zero - Starfleet could now roll out new equipment to its officers by, essentially, releasing a software update;
2) Improvements in sensor and CPU technology that permit heuristic image processing in real time, with the development of extensive rulesets around target identification.
3) Mounting horror over the pain and suffering caused by these weapons sheerly by accident led the Vulcan Science Academy to relax its usual proscription against weapons research in this one instance. The VSA convened a special task force made up of its best and brightest and gave it a truly difficult mission: find a way to make phasers safer... that humans will actually accept.

In the end, the solution the Vulcans presented was unique. Rather than building a conventional sight, trigger guard and safety into the weapon, they proposed taking care of the entire matter in the traditional Vulcan way: with software. The prototype they eventually offered Starfleet reflected the design aesthetic of Vulcan engineers who preferred to deemphasize the phaser's weaponized nature and give it the appearance of something more like a tool. The Vulcans succeeded so brilliantly that one of the Starfleet officers noted its strong resemblance to a form of handheld cleaning appliance once popular on Earth before janitorial bots became ubiquitous. As for its safety and aiming systems, the Vulcans provided a complex but comprehensive solution in a surprisingly robust package: a sophisticated wide-field sensor suite embedded in the muzzle of the weapon tied to a threat analysis and detection system that veered dangerously close to true AI alongside a variable-geometry emitter array that could fire a full-power particle beam anywhere in a 90 degree cone in front of the weapon.

The results in testing were dramatic. By simply pointing the weapon *in the vague direction of the target* and pressing the trigger button, the weapon would actually correctly detect the intended target using its pattern matching heuristics and calibrate the energy required to produce a certain effect on that particular target to achieve extremely consistent effects across materials, then direct the beam in the appropriate direction - and even track and hold the beam on target as it evaded, all without requiring effort on the part of the user. This effect can often be seen when studying recordings of Starfleet officers in combat during the period. For instance, here is an archival photo of then-Commander William Riker demonstrating the correct shooting stance with a Type I 'Cricket' using the new targeting system:

Note how the muzzle of the weapon is tilted upward while the beam fires at the target directly ahead. Commander Riker aims upward in order to give the phaser's targeting sensors, which are located just below the emitter, a complete view of the intended target so that it can attempt to detect the optimal point of impact.

Upon deployment of the Type I 'Cricket' and Type II 'Dustbuster' phasers, negligent discharge rates dropped by 90% overnight (thanks to a fingerprint sensor and drop safety added to the trigger) and friendly fire incidents dropped to almost zero with the weapon itself gaining the ability to detect friend from foe. The project was deemed an overwhelming success, so much so that the Romulans quickly stole and adopted similar technology. (The Klingons, of course, thought that - like most Vulcan ideas - it took all the fun out of life).

That's not to say the initial revision was without problems. The Vulcan scientists who developed the new targeting system neglected to consider cases where the definition of 'friend' and 'foe' becomes hazy, and as such the new phasers initially refused to fire on people wearing Starfleet uniforms - which poses significant problems in a galaxy that includes tailors trained by the Obsidian Order, not to mention all manner of mind-controlling, shapeshifting, and just plain weird lifeforms out there in the black.

Fortunately, the new replicators allowed Starfleet to push revisions to the design out rapidly (and coincidentally gave birth to a revolution in Starfleet uniform design, leading to a series of major revisions to the duty uniform over the course of just ten years, a process that would have previously taken that long for just one single change to be made). The design has since been deployed throughout the Federation and well beyond, seeing success in service from the front lines of the Omega Quadrant to the unknown reaches of Delta. The latest Starfleet service phaser incorporates adaptive emitter technology gleaned from the Borg, who are beginning to grow concerned that they, not the Federation, may soon be assimilated.