My choice for two people would be a Taipan 4.9 for the following reasons, it can be sailed either one or two up by either fitting or omitting the jib plus by adding a spinnaker you can sail it in the F16 class. They are reasonably priced and go like the clappers and are light enough to be able to be both carried and rigged by two people.
www.taipan.asn.au/home.phpWhile it may seem to be an expensive boat to buy initially this is tempered by them retaining excellent resale value.
If I had to pick a downside to this boat it would be that it has dagger boards and non kick up rudders, but that's the price you pay for owning a high performance boat.
Harry