Seemed to be more yaw component in the steep turns than I'm used to in powered aircraft (that rudder thing again)..is this my imagination, or is this actually the case with gliders?
Absolutely. Long wings will do that for you. Coming from a power background myself, I found that this was by far the hardest thing to (un)learn. That, and judging circuit height/approach/landing flare.
Actually, what you'll find is that it's not the steep turns per se that need a lot of rudder. It's the rolling into and out of a turn that creates the adverse yaw and needs a lot of rudder. But once you're in the turn with a stable bank angle, the need for rudder is a lot less.