It's about having a central focus. That the summary of the character was very superficial - especially when compared with ALL the other characters - and that the characteristics provided seem very disparate from one another, rather than form a cohesive narrative (i.e. one characteristic does not build, explain or shed light on another).
Yes, people have diverse interests in real life. However, real life does not make good storytelling. Real life essentially boils down to a series of random events, some predictable but many not; where as a hallmark of good storytelling features story devices such as foreshadowing, thematic arcs and allegories. As such, reality =/= fiction and that one cannot be used as a benchmark for another.
Ultimately, all I'm doing is trying to offer a critique of the character. If I've persuaded you, great. If I haven't, I hope my rationale and argumentation are at least understandable. It is hardly the de facto, one and only way to evaluate the character. When evaluating from her physical design, Sabine is pretty well executed - not just in utilising the advantages of CGI - but in conveying the core characteristics we are meant to take home for her. However, for me, having a clear, well thought out and sensible concept triumphs over physical design.
**Edit:**
Basically, my argumentation can be broken down as follows:
I can't readily see - and am not willing to blindly accept - how the character could come about. What we have with Sabine is a character who has a love for both, creation and destruction. If she grew up in a militant lifestyle with exposure to explosives and firearms, then why would she pick up tagging of all forms of self expression? Conversely, if the character is a street artist, then how did she get exposed to and become familiar with the use of explosives? Considering, she's been given a positive, upbeat personality, trying to merge the two seemingly contradicting traits into one character feels somewhat forced and artificial. Conversely, if the character had been given a more morbid/emo-esque personality, it would make more sense. Or alternatively, if her tagging was restricted specifically as a means to taunt the Empire by marking their triumphs.