There are definitely a lot of areas to consider regarding medicine, and
it probably wouldn't be a bad idea to run some of this stuff past a medical
advisor...and I probably will.
Insofar as crew relations are concerned...bear in mind that on any show,
a *lot* of that comes about as you introduce the characters, and the actors
get to know each other. Chemistry can't be predicted. What we do have, for
now, is that Laurel Takashima met Cmdr. Sinclair when she was working Mars
Colony security, and because she refused to go along with kickbacks to some
corrupt E.A. officials, was being held back. He was transferred there in an
advisory capacity, saw her potential, and pulled her back from some
potentially dangerous (and self-destructive) stuff she was getting into out of
frustration at being passed over repeatedly for promotion.
He's also known Garibaldi, the B5 security chief, for some time, but has
never actually worked with him for any prolonged period of time. He has
elected, over the objections of Earth Central, to give Garibaldi this
position, and it's his last chance to make good. But from time to time, the
requirements of a security chief don't reconcile with the needs of the
commander. He's only recently begun working with the resident xenobiologist
and the newly-arrived station telepath.
Is there conflict between them? Yes, at times severe. They all deeply
respect one another, but conflict arises as it must given the situation, and
the close proximity, and the problems they encounter. The basic requirement
of ANY good drama is interpersonal conflict.