This discussion makes me yearn for the days of olde when we had moorings...
I've only had a season and bit with Virago so far, so I too am learning just how much fun backing up a Contessa can be...but here's what I've found works so far for getting out of my slip (I mean getting the boat out of her slip!). It involves using the wind, and a bit of the old heave-ho as Jim R. described. I don't think it matters what side of the dock you use with this technique, although I suspect being port side to (as Virago is) helps because of the prop walk. Ok, here goes....
Lets assume that all slips accessable by foot are attached to the land at one end, we'll call this end the "shore", and that the other end is open to seaward and we'll call this end "seaward". This is written by a single-hander so there is no reference to crew. Crew is handy but not a given. What is a given is that these boats weathercock somewhat, that means that any wind that's blowing will move the bow downwind relative to the stern.
First scenario - wind is blowing from shore to seaward. Walk the boat out of the slip as far as possible, hop on and use reverse enough to get the boat clear of the slip and neighbouring boats. At this point you don't have to get the stern anywhere in particular, all you are doing is trying to get the bow clear of obstacles so it can swing down wind and point to seaward. Obviously the more room the better and if she's behaving back up as far as you can, but as long as the bow has room to swing clear you're ok. Once clear of the slip, put the engine in neutral and let the boat naturally weathercock in the direction you want it to go. It seems that sometimes the best thing to do is to remove the disruptive forces of the reversing prop. and rudder as soon as possible and let the boat sort itself out for a minute, then use the more effective forward forces when she starts to come around. This is also my preferred technique if the wind is blowing from the stern (blowing the boat into the slip) as the weathercock effect will help the boat back up straighter so I can go back farther for more swing room.
Second scenario - wind is blowing from seaward to shore. This has the potential to be way more embarassing. Again, the trick is to get enough room to let the boat do what it wants to do naturally, which means the bow will swing down wind. Get the boat out of the slip as above, but now the bow wants to swing towards shore. Usually the boat will want to reverse hard in one direction or the other, usually to port because of the prop walk. Let it. Keep the stern coming around hard until it is facing the row of slips you just left- what you are trying to do is gain swinging room for the bow. Once you are facing stern-to-stern with your neighbours a few boats down, use the engine in forward to initiate the turn out to sea. This is also my preferred technique for when the wind is blowing on the bow when in the slip because the bow will fall off one way or the other as I am trying to back out anyway, so I just let it happen and back all the way around to get room to manoever the bow. This is also the technique I use to recover when I farkle things up using the first technique...
This may sound like I have everything under control, which would be a lie.