In my experience, people with a strong conscience, or with strong moral principles, who are socially empathetic, and willing to help others even when this might come with a relatively high price to themselves, are clearer about what (according to them) needs to be done, clearer about which possible options to try to realize, and this makes them less likely to believe that it's up to them, or that they are free to do either this or that. When someone does something morally praise-worthy, they quite often say they had no choice, they only did what someone or anyone needed to do, and since they were present, that someone was them. I believe we need to take that kind of talk at face value.
The options we imagine we have are only imagined options. We are never completely free in arbitrarily realizing either this or that option. Anyone who has ever struggled with any form of mental compulsion or addiction knows this.
I believe that there are differences in sensitivity and perspicuity. Some people may have a clearer sense of moral direction (which may not necessarily be a good thing, btw). But this doesn't mean being more sensitive to or having a clearer sense of their "free will". We do not have any experiences of "free will". That is, we can have various experiences of being more or less in control (or not being in control) of our own behavior, our actions, our physical reactions -- and those could be called "experiences of free will" (or the lack thereof), but we never directly "see" that free will. What we perceive and feel, are just imaginings and feelings (hope, fear, smooth flow or inner conflict, dreams and daydreams).
A statement like "Cynthia perceived that it was possible ..." also seems a bit an abuse of language. We don't perceive facts. We assert facts and theories. I perceive a grey cat. But I do not perceive the fact that the cat is grey.
In regards to the value of "seeing clearly", there is a beautiful autobiographical short story by Isaac Babel about the merely relative value of clear, sharp lines, Line and Color. When the narrator tells Kerensky that he needs a pair of glasses to see reality as it is, in sharp lines, Kerensky counters with
You can keep that line of yours with its repulsive reality. You are living the sordid life of a trigonometry teacher, while I am enveloped by wonders’ even in a hole like Klyazma!
The whole anecdote, especially with its ominous end, commenting on Trotzky taking the stage after Kerensky, at a mass rally half a year later, has more philosophical depth than most philosophical musings. And since it's merely literature, it also has the advantage that it seems to leave everyone free to make up their own mind.
The question posed is interesting since it is situated in a fuzzy borderland between philosophy and psychology. It probes if differences in how agents subjectively experience possibility might be relevant for the free will debate. It seems to suggest that (or ask whether) disagreements about the so-called problem of free will might be partially due to people projecting their own particular mode of experience of having multiple alternatives onto reality.
Now, it's clear there are psychological differences in this regard. There are psychological studies about this, trying to correlate a subject's sense of agency - the feeling of being in control, being the author of one's actions - with the number of available options, with locus of control (whether one sees the outcome as dependent on or caused by one's action), with explicit beliefs in having free will, and also with feelings of being free, unconstrained. Some somewhat alarming experimental studies show that is is relatively easy to trick people into feeling/believing that something that they see happening is controlled by them even though what actually is happening is demonstrably outside of their control and may even be random. See: illusion of control.
The question then is: Does this have any bearing on the philosophical problem of free will? Answer: Yes, it does, though it may not quite settle all metaphysical issues (if one believes there are any left).
First of all, I think, it shows that the belief that one "could have done otherwise" (looking back) or the belief that any of a set of alternative options is "available (up to me to realize)" is not some uniform given that has the same content or valence for all individuals. In this regard it's also important to see that "seeing more alternatives" can be correlated both with a stronger feeling of agency (and responsibility) (for some people) and with a weaker one (for others). An extreme case is described in Musil's _Der Mann ohne Eigenschaften_ (The man without qualities) in which the protagonist, Ulrich, sees himself as a Möglichkeitsmensch, someone with an overwhelming sense of counter-factual possibilities, a sense which does not make practical life (and relations with other people) easier, but rather paralyzes him.
Both decisiveness and paralysis can result from a richer, stronger modal awareness. This at least somewhat undermines phenomenological based arguments for a hard, libertarian free will. But the problem here shifts from "do we have free will" or "is free will real" to "what matters for (healthy, normal) agency". We want to be able to see multiple options (but not always), we need imagination, but we cannot deal with too many, since that can also make decisive, "free" action just as impossible as having no options at all.A
(A) The same pyschological minefield is the subject of Barry Schwartz, The Paradox of Choice - Why More is Less, 2004.
Musil's Man Without Qualities contains a lot of explicit philosophical musings. The classic problem of free will is the subject of the chapters about a murderer, Moosbrugger.