Yes, i have seen other nasus build and understand your choice, but Nasus already heals so much with his passive, and given an bloodthirster he will get even more, so i find spirit visage unneeded, but this is not a take-this-guide-or-you-suck-guide.And why cooldown boots? If you crit your q you don't need that increased cooldown, and you can get masteries for that too, and blue buff for increased cooldown as well, so i find those boots unneeded, and ninja tabi gives me that 1/8 chance to dodge an attack which will drastically lessen the damge in teamfights from ad carries on Nasus. You just have to find out what works best for your playing style, so, I'll think about it... Might try it, thank you for sharing this ^^

i like to get spirit visage or ionian boots of lucidity sometimes. (i rush sheen) if i am still in lane phase and have enough gold for it