Her core personality stays the same between the different appearances - they are literally just her body changing around her - which can lead to some rather incongruous combinations. However, this has been happening to her for a while now, and she has found that people tend to expect different things from her depending on how she speaks, or more accurately accept different ideas, so she does modify how she interacts somewhat. For instance, Thunder and Fire are never good for sympathy, so she's stopped trying to explain her sudden appearances in houses using the 'I'm just an innocent girl who stumbled in here, no I don't know how I got here sir' line that works so well for Force.
EDIT:// Or in short, what NGP said
Also, it isn't a coincidence that her most regal and tallest appearances coincide with the domains of her primordial deity/husband