Deltabot build area.  What's a good diameter?

Deltabot build area. What’s a good diameter?

330mm means that the Replicator2 print area fits comfortably inside. Is that big enough? Diameter of the printer is (high estimate) 150mm over the printable area - making the overall diameter about 480mm or 19 inches.

Other considerations are how long the arms need to be, of course - bigger is harder in many ways.