I dont understand what's your problem with fire main. For me, oboro is actually a buff in most cases. You can cast 1st mystery r1 and r2 in addition to your normal combo starter, also +1 auto but no imprison. In normal 1v1 pvp I actually feel stronger with current oboro than before. 9tails already looks like oboro > unparalelled. Death mirage can be tricky, since it was used in addition to tag for Cat, to procc dodge of dodge ninjas so theres a nerf, but a reliable source of tags opens up a lot more hidan and minato teams. Test it first, then complain.