I don't think any of these terms are particularly useful, because they assume a sort of governmental structure and set of norms that was quite different from what existed in antiquity. Within the context of ancient Mediterranean politics, however, Caesar had a very well worn archetype that describes him well: the populist tyrant. The examples from Greek history are legion, from Peisistratus to Agathocles, and while somewhat less common in Roman history we can look at, say the reaction to the Gracchi to see that the fear at least was highly present. And of course in later times we can see the mold fitting around people such as the Medici.

As for his particular motivations, that is a bit more difficult to suss out. Adrian Goldsworthy's Caesar makes a very compelling case contextualizing him within the politics of the day to argue that he was essentially a conventional Roman politician who, because of the extraordinary times, was driven along a course towards extraordinary ends. I think this interpretation should at least be the foundation f any reading, but the arguments over Caesar's nature go back literally more than two thousand years, so there are plenty of other ways you can take it after understanding him within the context of the times.

Could you expand your question? What do you want to know about Julius Caesar?