You do know that this thread had been dead for almost 10 years?
I've spent quite a number of years sailing a Vanguard, and Jeff_H is correct. Terrible in light air, slow, and develops quite a bit of weather helm in a breeze unless you reef early. Downwind in a breeze can take quite a bit of effort to steer. Depending upon the point of sail, wind speed, and waves, I could get the boat to steer with the tiller free, but I've sailed other boats that were much better.
Your Meridian is probably closer to a Vanguard - the Chesapeake 32 was a centerboard boat. And like the Vanguard, the Meridian is no speedster, with a PHRF of around 285.
As far as mainsails on the old CCA designs - these boats were designed for large overlapping jibs - around 170%, due to the way the additional area was treated by the rating rules. A more modern design not constrained by the CCA rule would have put more area in the main and used smaller overlaps in the jib.