I'm surprised that the SA/D ratio is so low on the Southern Cross 31. That doesn't sound right to me, but I have no first hand knowledge. Might be worth a double check. Is this not the Gillmer 31, built by Ryder? If so, there should be some discussion in Ferenc Mate's "Best Boats to Build or Buy".
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I will shamelessly put in a plug for our boat model, the Pacific Seacraft Crealock 31 (not to be confused with the PSC Mariah 31). It has the attributes you describe, in the size range you are looking at.