My favorite composer, Igor Stravinsky, wrote in his Poetics of Music, that before he could begin a new composition, he first had to establish the parameters for the composition. Otherwise, the possibilities were infinite and he could not proceed.
In this digital age of photography, now, anything is possible. Yesterday, when I downloaded the latest PS, LR and ACR upgrades, I could not resist looking at the Sky Replacement feature. I was, at once, fascinated and appalled. I could, with little effort, take an unremarkable landscape and create an "epic" sunset, rainbow, or dramatically clouded sky. To me, this is a sophisticated form of Clip Art. Is it wrong? For me, if you disclose what you did, then no. If you do not, then you should identify your images as graphic art. Dropping in a sky is no different than adding an exotic flower, a herd of Bison, Mt. Everest, the Starship Enterprise, point made.
"Bucket List" photography, sadly, has evolved from capturing your experience at iconic locations, to "Epic Obsession". If your one-time visit at the long-anticipated location is not "epic", are you now disappointed? Are you there to immerse yourself in the beauty, the moment and environment, or are you seeking to generate yet another, "Awesome colors, Dude" post on your social media site of choice. If it is necessary to alter the image so dramatically, perhaps it is time to re-evaluate why you are taking photographs. This should not be a Saturation Slider contest.
For me, my guidelines are these: I am there to capture the moment, the mood and my visceral experience of that moment. I want you to feel and see what I felt and saw. Will I remove minor distractions? Yes. The distant power line, the styro cup I didn't see at the bottom of the pond, the tiny hot spot at the edge of the frame, yes. To give the viewer my three-dimensional experience requires that I draw them into my two-dimensional image and view the whole. Similarly, my abstracts must be photographically honest. I will not add elements. Will I process colors and textures? Yes. Add what was not there? No. These guidelines give me comfort and gratification.
I believe it is incumbent on us all to continually assess what we are doing as photographers, and decide what our purpose is in both the capture and the presentation. Now that anything is digitally possible, it becomes far more challenging to clearly define our work and our style. That difficulty and challenge when met, creates true artists.