There are indeed multiple sight pictures that can be used successfully for the situation that you are facing. Time, distance to target, hit zone size, acceptable hits are some factors. Say up close from 3-5 yards you may need maximum speed and only need hits in the A zone of say an IDPA or IPSC. A skilled shooter may only need to target focus, looking through the sights with soft focus to achieve all A's. As distance increases or acceptable hit zone shrinks alternate sight pictures up to and including pure front sight focus may become necessary.
We often refer to it as "seeing what you need to see, to get the hits you need to get". Again this can vary from person to person skill level dependent. Understanding this about ourselves is important. For many newer or lesser skilled shooters we of course advocate a stronger front sight focus. This is where we start with new shooters and hope to progress them into variations of sight pictures as skills increase.
Riding the trigger only to reset is not a good thing. Pining the trigger is generally not a good thing. We should be prepping the trigger and resetting and re-prepping the trigger during the recoil phase. Once the sights lift we should be resetting the trigger and all of the pre-travel of the trigger should be removed. We should now sbe at the edge of sear release so once the sights settle we should be breaking the next shot as needed. This like many other things has caveats to it in that the trigger type or pull weight can be the more determining factor. In general with say a Glock as an example, if you can hear the audible reset of the trigger after you fire each shot, your not doing this technique correct.
Coming all the way off the trigger is of lesser importance and is very much trigger dependent. With say a 1911 with a light trigger, short pre-travel, short sear movement, virtually no over travel, very short movement to reset and virtually no post travel, I will come all all the way off the trigger. This is a pure technique and I do not refer to it as slapping the trigger. That connotation is mostly taken poorly in context by a new shooter and replicated incorrectly because of this. Now with a Glock I will go beyond actual reset but with so much post travel, I don't tend to lose contact with the face of the trigger. It is a more precise technique IMO when it comes to precision, but it can take more technical skill.
I generally ignore any article that discusses "fine motor skills" as it is often misunderstood and presented or more so regurgitated from others in the incorrect manner that has been around shooting particularly LE and the psychology of body alarm, reptile brain, fight or flight response in humans.
This is a good thread that talks about vision and sight pictures. Highly skilled shooters may naturally progress to these vision related techniques discussed in this thread on their own accord but may not actually know what they are doing from a technical aspect or description. While getting a host of newer shooting enthusiasts is slowing down conversations quite a bit, pistol-forum has some of the most technically correct, cutting edge shooting information out there, especially for shooting handguns. Probably one of the 3 technically best shooting forums out there. There is a ton of great technical info in the resources areas or stickies.
https://pistol-forum.com/showthread.php?10210-Vision