To uumlaus' point, these functions don't operate on their own, and all of the other functions influence how they will play out.
Also related to his point, other functions can and do impact ones' personal value system and how one 'decides' what they value. I have used this example often in discussions like this on here, but it's because I think it serves a purpose: My ISTJ mother, who has zero Fe, is very much a product of how she was raised, and the generation/community/value system she was raised in. She is more 'conventional' in her beliefs of right/wrong, and what you should and shouldn't do, as per how she was raised and the lens she looked through via growing up in the 50's and 60's, than I am having grown up in the 80's/90's. My values/beliefs have often diverged greatly from those of my peers, and I don't think I'm deluded in thinking that many of my values are self-derived, after much reflection.
I think it is why I prefer to view Fe in a more utilitarian/pragmatic sense, rather than tying values into it. For myself, Fe is about interpersonal dynamics, and weighing other peoples' needs/views in the context of the 1:1 convo we're having, or the work environment I'm trying to work in. Taking things as they are, and working with that reality, trying to morph it slowly if I don't agree with it as it currently stands (and I often don't agree with it, in whatever context I find myself in). Maybe it's that from the outside, because I am trying to work with it, it appears I must therefore fully buy into it. This is not the case. It's more that I view all of it as the current 'reality', which I HAVE to work with - take it as it is - and then try to enact changes based on how it is and where I think things should move, esp. if I think things are really messed up as they currently stand (these comments are mostly applicable to a larger group - i.e. a Work Environment). It's like a big organism composed of a bunch of individuals who I know have their own individual value systems, some aligning with the 'group values/culture', some who are not aligned, and everything in between.
I view my own values as distinctly separate from those of everyone around me, and often-times I don't find my own values relevant to the situation I am in (i.e. I'm not going to wax poetic on nature/the environment while I'm on the job in a corporate setting, because I'm here to do an analyst job tied to something utterly different, with corporate politics). And, in the end, it's about my trying to get along with people to accomplish the task at hand. There's nothing more than that. It doesn't mean I don't ruffle feathers or raise red flags, or make it clear when I disagree with some aspect of the culture, it just means that I am distinctly aware of what everyones' trigger points and concerns are in the environment, so I know what they want addressed. I'm also aware of how immersed everyone is or is not in the 'culture', and if I try to push at it many times and it's unmovable, I either need to continue to try to enact change in a more long-term mode, or I need to leave if I really can't stomach it. Sometimes the latter is the case.
I'll be sensitive to those dynamics so as to accomplish what needs to be done, and get the projects rolling forward. I'm using work as an example because I think it's relevant; I absolutely don't take ON the values of my organization, and am in fact many aspects rub me the wrong way and I have pushed back and questioned a fair amount, but you can only do so much and change of a cultural sort takes a long while to take hold, if it ever does. So I either roll with it to a degree, if I recognize it's never going to change and am generally 'ok' with the gist of all of it, or I leave if I'm not.