The initial capture of the photograph (the RAW data recorded by the camera) and its subsequent transformation into an image (the final product achieved through editing) are of equal importance to me. When I push the shutter button, I often think of it as collecting data. I usually capture multiple frames of the same composition with different shutter speeds, or other altered camera settings. These frames are my clay.
I then use the tools of post-processing to sculpt this clay to try to present as full a representation of what I experienced as my skill will allow. I frequently use editing as a way to try to close the gap between what our brains can do and what our cameras can do. Though this editing can be elaborate, its goal is not to mislead but to convey a more complete sense of place, and often motion, than a single camera frame can convey. Although there also are times when I just want to make something cool looking. When that happens, it's pretty clear that it is not a "realistic" photograph.
For example, our brains can take in a surf scene and register both a wave crest with drops of water frozen in mid-flight and the soft trails left by receding water. Our cameras are not so flexible; for them an individual frame records only one or the other. Through editing, I can shape my clay and combine elements of both the fast and the slow into one image. This conveys a more complete sense of “waveness” than is possible with a single frame.
All that said, many of my images are "traditional" in that they reflect a scene captured and displayed with minimal editing and limited, if any, blending or merging of frames. These are "real time" images that display - always subject to some degree of artistic interpretation - what was there at a particular moment.
When the editing is more elaborate, it sometimes means adding and combining elements, as in the wave example mentioned above. Sometimes it means removing things - often unnecessary or distracting details - to create a more abstract image. The goal then is to limit the presentation to the core elements of the scene. To do that I use long exposures, Intentional Camera Movement (or "ICM"), as well as a range of editing tools. This lets me “paint with a broader brush“ than does a more traditional approach . I think of these as "slow time" images.
We all come out in our own place on how we approach the "how much is too much" question. I generally (although not always) try to stay within the bounds of "this could have happened in this time and place, even if it wasn't exactly this way at this moment" school. I undertsand those who criticize that approach. Much of my decision is aesthetic, but there's no denying that I love exploring what my computer can do and, well, one thing leads to another. Ultimately I'm trying to create an image that is visually interesting (if not always entirely "appealing") and makes the viewer feel something in response. Go forth now, and find the way that works for you.