I think that those guys won't be hit very hard. I expect pl to be nerfed in a way that makes the illusions hit buildings for very little damage, but no actual changes to his ability to fight heroes, Naix to have some numbers tweaked (maybe rage duration decreased for about a second or two), Nyx maaaaaaaybe have his mana costs increased (I think IF will just wait for players to learn to turn off their AoE when there's a nyx near), and gyro to be left alone. These guys might be a bit too good, but a few buffs here and there should be enough to make them fall a bit in favor of others.
But lone druid and kotl are getting the nerfhammer for sure. What a skilled player like bulldog can do with lone druid is just way too much for it to be allowed maybe the teleport or resummon will be nerfed in a way or another. And kotl antipush abilities are way too good, but a simple "Half damage to creeps" on illuminate would be against the concept of the hero, so I don't know what IF will pull.
I still don't see a way to fix the gayest lane in asia (kotl-pl) though.
But let's be honest, right now the hero pool is enormous. There ¡s no longer a Lycan first ban, but dozens of heroes that nobody wants to face, even if the opponents can't play them well.
If [A] got such amazing plays on G-1 finals was because they can play any hero really really well. You ban Druid and NP? Ok, maybe bulldog doesn't have his core heroes, but you just let Akke chen and wisp through. Wisp and chen out? Well, let me show you why S4 is known as son of magnus. Banning every single Loda hero, including rikimaru? RNGG says fuck you.
There are tons of viable hero picks. And just wait until guys like centaur, drow and troll get in, it will be even bigger (Troll-wisp-tiny pleasepleasePLEASE). And new strats introduce new heroes every week (DD treant, [A] Ogre). I think that this balance patch will be more about buffing power creeped guys like lich or CM than nerfing PL.