Pantheon needs to be nerfed into unviability similar to pre rework Poppy
Pantheons early game is to the same thing that pre rework Poppys late game was. You are legitimately left with one choice: "can I tank his spears or not?" Past this point, there is only one other means of dealing with him and it comes down to whether you outrange him entirely or not.
Prior to s6, one of the things that was a viable solution was to run cloth5 and out sustain his mana pool and that worked pretty effectively. His lane phase was still brutal but you could actually play around that. It wasn't easy but it could be done. Now, with meditation and corrupting potion, pantheons mana problems are gone. You can't rely on outsustaining his mana pool. You can't even be around him at 50% HP if he's running ignite (most of them will run ignite) because of the crit execute passive on his E towers won't protect you either because he will block two tower shots.
How is this okay? He has remaining the winningest top laner for months now with a fairly moderate pick rate (most sites have him between 7-9%). Most people on this board don't know how to abuse his lane phase because they think bullying means you sit on minion waves and auto attack them every chance you can and then randomly die to minions. However, anyone with half a brain realizes all you have to do is spam Q off cooldown from max range and save stun for any potential engage. If you're melee or even short ranged, there is legitimately nothing you can do about this. While this isn't old yorick levels of zero counterplay, it's pretty damn close.
There are a small handful of champions who can survive Pantheon but that's not the problem. Considering his pickrate and winrate for the last forever, that doesn't seem to matter either. Not to mention, you just buffed him with lethality buffs. And that doesn't justify lack of balance either because OP champions have always had some lane counters so that's not even a valid argument. Nor is the argument that he "falls off" - which by the way, his winrate doesn't dip below 50% until 35-40 minutes, how many games goes that long anymore? He needs to be dumpstered until he's reworked. I shouldn't have to waste my ban on him permanently because I actually want to play the game.