Nasus Suggestion for slight spirit fire adjustment

I feel Nasus is decently balanced considering how hard it must be to balance how he scales. He does just bad enough early game to not snowball all the time or make too many champions bad against him and he hits like a truck and is tanky during the mid to mid end-game if things go well for him. He’s a bit of a lottery, either you get one of the most powerful midgame champs or a fairly weak tank/half-tank that can’t do much. I feel this is how he should be, but his endgame has suffered for quite awhile. If he’s been able to get 500+ stacks I think the other team should be running from him but often he drops off because while he gets a ton of damage so does everyone else currently at 35+ minutes so what I’m proposing is something intended to buff his endgame without needlessly improving on his 1v1 ability and to improve his team fight worth more endgame. Spirit fire is fine early and mid game but end game it’s just a joke, the enemy team will often just ignore its near useless damage while it drains Nasus’s mana pool. It’s really only good for the armor reduction and the potential to nab a kill from someone who just barely escaped with their life. After a lot of thought I think I came up with a good idea that seems to work both in the potential to balance the move and fit with his character in a way that isn’t clunky or out of character. Add this passive or a slight variation: Spirit fire gain’s 10% increased base damage and loses 5% ap ratio for every 100 stacks Nasus has. The ap reduction reduces the likelihood that Nasus would just switch full AP end game in order to poke because he would sacrifice a lot of survivability for very little damage. The 10% would be nearly insignificant early and could build to significance at the end for (assuming maxed spirit fire) 100% at <100 stacks 215 burst damage 43 damage each second 60% ap ratio 12% dot ap ratio 110% at 100 stacks 236 burst damage 47 damage each second 57% ap ratio 11.4% dot ap ratio 121% at 200 stacks 260 burst damage 52 damage each second 54% ap ratio 10.83% dot ap ratio 133% at 300 stacks 286 burst damage 57 damage each second 51% ap ratio 10.28% dot ap ratio 146% at 400 stacks 314 burst damage 62 damage each second 48% ap ratio 9.77% dot ap ratio 161% at 500 stacks 346 burst damage 69 damage each second 46% ap ratio 9.28% dot ap ratio 177% at 600 stacks 380 burst damage 76 damage each second 44% ap ratio 8.82% dot ap ratio 194% at 700 stacks 419 burst damage 83 damage each second 41% ap ratio 8.38% dot ap ratio Considering his passive is “Soul eater” and his weapon’s name is “Soul Staff” that gets stronger with more stacks from kills and his ‘q’ ability using Soul Staff is called Siphoning Strike drawing to mind stealing power from kills or enhancing the staff with more spirits, then it makes sense that Spirit Fire which is made by spinning his Soul Staff would improve with more spirits farmed. The reason I didn’t increase the loss of ap ratio was because I didn’t want this to become a nerf to AP Nasus whoever likes to play him or for ARAM, either way, I hope riot takes this suggestion and tweaks it however necessary to then help Nasus be the true end game monster he is supposed to be.