Of all the Reinin dichotomies, the Aristocrat vs. Democrat is the one that, to me, tends to stand out the most in interaction. It's not one of the more "apparent" dichotomies, but in my experience it is observable in people's styles of communication and attitudes towards social interplay. I wanted to highlight some of the traits that stand out to me as distinguishing Democrats and Aristocrats
Mutual or Common Experiences
This distinguishing trait is most observable, IMO, in Democratic Extroverts and Aristocratic Introverts.
In communication, Democratic types are the most likely types, IME, to try to overtly establish or build off of the idea of a common or shared experience. Common phrases are things like: "You know how when you shower for too long..." "Have you ever noticed..." "Is x like this for you too?" Basically they will assert an experience and put it "to the jury" as to whether or not this is commonplace, expected, mutual, etc. The basic assumption of the Democratic quadras is that each individual is different, that each person acts on their own and is simply one of many extant individuals, so this is an attempt to "translate" the inherent differences they observe.
In contrast, Aristocratic types operate with the assumption that certain people are either inherently similar or different. With people to whom they feel they relate or share certain things, they speak easily of experiences that they assume to be mutual, omitting things that the other is assumed to know and making statements or judgments based on what is taken for granted as common knowledge without drawing any attention to it; they assume that people either speak their language, or don't.
In activities like public speaking or teaching, there is a distinct difference in the attitude of presentation of information.
Democrats tend to have a casual, more lightheartedly performative approach to self-presentation. They are more likely usually very explicit or presentational, making more of a point to introduce themselves, perhaps saying something moderately personal, awkward, or funny to break the ice. They generally speak about their own ideas or contributions or something they find of personal interest, often using anecdotes to help people understand the specific applications of what they are saying. They are more likely to involve the crowd or "break the 4th wall." This gives them a somewhat stand-alone feel, appropriately; when we see them speak, we assume that nobody came before them, and nobody will follow them. They are remembered for being themselves and embodying their own viewpoints.
Aristocrats, by contrast, can seem low key in presentation, because they assume a certain pretext for their words; they speak as if they require no introduction, perhaps even seeming arrogant to those unfamiliar with them. They are more likely to speak with a kind of contextualized gravity, as a priest giving a sermon; they sometimes use anecdotes to make the tenor of their speeches more personal or serious. More common topics are things that they feel are relevant to their direct audience, or things they feel "should be heard." When they speak, they speak for something else; when you see them on the stage, you see not one person speaking, but the conduit for the people or ideas that are "behind" them, that they attempt to embody and represent.
These are just a couple; if people want to blurt out some ideas and help me get the juices going I will try to do more.