I have 255/40 & 295/35 currently, somehow an odd size but looked great if you ignored the height.
AlWakRa 370z's Journal - PW from Qatar
I think your best bet for more meat will be 255/40 & 285/35, but not sure of front rubbing even though I run +22 wheels in front without issue, or 265/305, but will be a little shorter then mine but meatier than yours.