The AFR heads have great flow rates. Particularly on the exhaust side. The poor performance of factory chevy heads is one reason that dual pattern cams have been so popular with chevy lovers. But with the AFR heads, you don't need to worry about a dual pattern cam because the exhaust flows so very, very well. I have two suggestions. . . . both are Comp Hydraulic Rollers (I know, that breaks the baseline rule, but I think you'd like the results). Have Comp grind a custom with the Extreme Energy 230 degree lobe (or the Extreme Energy 224 degree lobe) on both the intake and the exhaust. It seems strange that a single pattern cam would seem out-of-the-ordinary, but for a chevy these days, it is. This kind of a grind allows a little more than you would otherwise take on the intake side, without over-doing the overlap and creating a loss of vaccum. At least, give a single pattern some consideration. And with a roller, you have less worries about failing the break-in cycle and flattening a lobe early the life of the engine.
Whatever you do -- Good luck!!