I never thought Kendra was judgemental. Well, she may be, but it's due to her upbringing.
She was trained since she was a child to be a Slayer (which always made me wonder: what happens to girls like her if they are never picked to be a Slayer? Do they fight evil or are they trained till they are too old to be a Slayer?). She was raised to obey orders, to stay away from men...That's all she knew before she came to Sunnydale. So I can understand her reactions when she appears in Buffy's world, because it's all so different for her! Kendra was raised to believe Vampire=bad. Slayer kills vampires. And that's it! It's a very black&white way of seeing things but that's the way she grew up!
And, she opens her mind when she realizes that everything isn't black or white. In a few episodes, she really grows up on me. And I love how she finds a reason to fight when her only shirt is torn! And when she gives Mister Pointy to Buffy, awn!
I was never bothered by her accent, just thought it was funnily cute!