What skills are needed to sustain a research group?
I try to only work with people who are capable of excelling in all the skills needed to perform and write up high-quality research.  

That's not to say that some of them (particularly students) won't need training in those skills in order to excel, of course.  But I definitely don't believe in having 1 guy who only collects data, 1 who only analyzes data, and 1 who only writes (or some such scheme).  If you pursue such a scheme, you may be crippling people.  They'll likely have a hard time in their next job, when nobody holds their hand through the other parts.