Though Caitlin left B5 to pursue offers to star in romantic lead
parts, nothing to do with typeasting...your general concern is correct.
We've tried to help avoid that on behalf of the actors. For instance,
visually, you can hardly recognize Peter Jurasik in makeup; ditto for
Andreas and the rest of our alien cast. This shouldn't inhibit their
work in other areas (as opposed to seeing someone very recognizeable, but
with pointy ears, which caused Nimoy great trouble for a long time).

In terms of the human characters, I've tried not to wrap any of them
around one specific character trait. They range from serious to comic,
and do different things.

Typecasting is a real concern, and it has to be addressed by those
who make the show.

jms