Nasus should lose his Q stacking, it is giving him power that wasn't meant to be there.
Honestly, his damage in his spells and his passive are OK but being able to dish out ALL of that damage in 1-2 seconds WHILE being able to sustain through the fight with his free lifesteal passive(which also applies on your Q's) is absurd.
Riot has even said that Nasus Q stacking was NOT intended at all, the fact that he can hit u with 3 Q's in 1-1.5 seconds shouldn't exist.
The fact that he can get rid of his R animation and activate W all at the same time with his E shouldn't exist.
Nasus can use all of his spells and 3 empowered auto attacks within 2 seconds, faster if the player is very used to Q stacking with Nasus.
This shouldn't exist at all, it gives so many other champs that a huge disadvantage as they don't have the luxury of being able stack their Q's infinitely.
Now he shouldn't just have his Q stacking removed then left in the dumpster, as I'm sure it MIGHT do that, he should be left in the state with no Q stacking for 1 patch to see how he rolls, if his win rate does somehow plummet and all of the actually good Nasus players are starting to have immense troubles using their Q, then he deserves buffs so that he actually becomes a bruiser with sustainability in fights, not a bruiser with the burst of an assassin and sustainability of a Bruiser.