With today's highly modified malts, I feel you can get away with brewing damned near anything on a single-step mash system. Just use plenty of crystal malt for body and mash higher for a fuller finish. Spices? You could spice a weizenbock, I suppose, but I'd just use WLP300 or something akin to that for the phenolics you'd get in a standard hefeweizen. Just my $0.02.