Describe Theseus's character. What sort of leader does he seem to be?

Theseus is a patriarchal ruler who tends to expect women to fall in line when it comes to love and marriage. For instance, Hippolyta, his fiance, was queen of the Amazons until he forcibly took her from her home. As he puts it:

Hippolyta, I wooed thee with my sword

And won thy love doing thee injuries.

 However, he expects she will fall in line and be happy with marrying him:

But I will wed...

Theseus is a patriarchal ruler who tends to expect women to fall in line when it comes to love and marriage. For instance, Hippolyta, his fiance, was queen of the Amazons until he forcibly took her from her home. As he puts it:

Hippolyta, I wooed thee with my sword

And won thy love doing thee injuries.

 However, he expects she will fall in line and be happy with marrying him:

But I will wed thee in another key,

With pomp, with triumph, and with reveling.

Likewise, when Egeus complains to him that his daughter, Hermia, refuses to marry the man he has picked out for her, Theseus supports the patriarchal order, telling Hermia

 Be advised, fair maid:

To you your father should be as a god

When Hermia says she wishes her father could see Lysander and Demetrius as she does, Theseus tells her that her duty is to see the men as her father would like her to:

Rather your eyes must with his judgment look.

He then tells her that if she doesn't marry the man her father has chosen she'll either face death or be shut up in a nunnery devoted to the goddess Diana. He seems to have little capacity to view love through the woman's eye and appears to work through coercion rather than gentle persuasion, though he does say he has no choice but to uphold the law. However, even if he is forced to uphold the law, he doesn't have to tell Hermia that she should treat her father as a god. 

Theseus's view of love is pragmatic as well as patriarchal. He famously likens lovers to madmen and poets, saying they're all out of their minds. 

However, near the end of the play, he does allow Lysander and Hermia to marry. And he shows tolerance for the Mechanical's play, understanding that they have good intentions even if they can't act. He seems, if a bit patriarchal at times, to be a practical and reasonable leader whose kingdom runs well and in an orderly fashion.