When I first came to the forum, I'd just started playing FM'05 and was frustrated because my team kept arguing their way into red cards. I was
sure it was a bug.
It turned out, it was my choice of captain.
I'd picked a high Influence guy with low Composure and (I suspect) the "Argues with Refs" PPM.
I switched to a lower Influence captain, and immediately my side stopped getting sent off, dropping from maybe eight or nine sendings-off in a season to zero or one.
So, I think captain is a
very important decision, long-term, and as a result I've tended to overlook the short-term impact to make sure I've got the guy I want in the long-term.
For my thoughts on what I'm looking for in a captain, see
Selecting a Captain