Kog ideas
(100% credit given to Rebonak on his original thread http://boards.na.leagueoflegends.com/en/c/gameplay-balance/EKxEEbVt-remaking-the-remake-or-a-kog-for-everyone?)
Before the remake went down Kog was being pulled in three directions. His Q and W made him the tank-buster Marksmen along with Vayne. His W and Q also made him the long range machine gun Marksmen (Trist used to fill this role as well, but Riot nudged her over to a siege focus). Kog's Q, W ,E and R all gave him solid poke. And of course his Passive is a potato which has absolutely no relevance to his kit.
When the remake went Live, Kog could reach his old tank-busting power if he went with an AD heavy build. Since the removal of the AD ratio on his W, Kog's ability to tank-bust has been heavily nerfed. In terms of %HP damage done over the duration of the skill, we're talking half the damage.
In like manner, Kog's poke took a pretty heavy hit when his Ult was turned from a poke tool into an execute.
So Riot decided to focus in on Kog's machine gun aspect with laser-like focus-
-but still kept his potato Passive for some reason.
With the suggestions here, I want to pitch a Kog that should make all of his old players happy. Or at least all of his old players a little more happy. Some people really hate the new W, so there's not much to be done about that. Anyway! On with the show. Fully remade skills will be spelled out. Modified spells will have changes noted. Goals
Make all 3 builds viable

Old Kogmaw

On-Hit AS Kogmaw
AP Poke Kogmaw
(Builds are not exact, but in general)
_P - Eldritch Enzymes _ TLDR: Kog'Maw attacks deal %max hp
Kog'Maw's basic attacks have no Bonus Attack Damage ratio. Instead, his basic attacks deal bonus magic damage OnHit equal to 2% plus (percentage) per 100 bonus AD of the target's maximum HP. This OnHit damage can critically strike for (some amount less than 200%?).
Want to play Tank-Buster Kog? Build him AD. Do note that Kog is losing the AP ratio on his %HP damage. That's quite intentional. AP Kog isn't the tank-buster after all. This also means Kog has fairly low damage against Towers when compared to other Marksmen, but his ability to take monster objectives should be quite a bit higher. This also means that, barring Gunblade, he gets very little benefit from Lifesteal. How's that for clear strengths and weaknesses?
Q - Caustic Spittle: Kog'Maw's Q Ratio is increased
AP Kog is losing the ratio on his %HP damage, so he'll need something else to make up for it. Before it was turned into a skillshot, his Q originally had a 0.7 AP ratio, so that seems like a good place to start.
W - Bio-Arcane Barrage: TLDR: ** Kog'Maw's W is a toggle. Off = Nothing <---> On = Double AS + Self slow + 55% AA Dmg**
Toggle Off: It does nothing! Who do you think Kog is, Jinx? He's not getting something for nothing. Toggle On: Kog'Maw doubles his attack speed and attack speed cap in addition to gaining significant attack range. However, he slows himself by 75% and reduces the Base Attack Damage ratio of his basic attacks to 50%. After activating this skill, Kog'Maw gains (amount) additional attack range over (duration). Cooldown of 6/5/4/3/2 seconds, 40 mana cost activation.
Ah, Kog's double attack speed buff. It comes a toggle now, but while it's on Kog gets a pretty crippling slow to really hammer home the idea that he's a turret champion. The initial range buff he gets should be pretty solid, but the longer he keeps it on the more range he gets. This is to encourage Kog to set up in a good position and start shelling his foes while his team does the whole 'protect the Kog' thing. Obviously I have no idea how much range would be reasonable, but I'm sure Riot could find a solid value.
As before, if Kog wants to do the whole long range machine gun thing, attack speed and OnHit damage is the way to go.
_E - Void Ooze: _ Slow increased to 40/45/50/55/60%.
Just a straight forward buff to Kog's ability to fend off people charging straight at him. With his immobility amplified, his slow could really use a bit of love.
R - Living Artillery: TLDR: AP ratio static. Bonus AD ratio goes to %missing HP
This ability's AP ratio no longer increases against foes with low HP, instead remaining at a static (0.4? 0.5? 0.6?). This ability's Bonus AD ratio no longer increases against foes with low HP, instead it deals (percentage) of the target's missing HP as bonus magic damage per 100 bonus AD.
AP Kog poke-monster is back in town! AP Kog's execute damage is MUCH lower than what AD Kog boasts, but he actually has the ability to snipe full health targets and do something other than waste his mana. In the same fashion, bonus AD gives the skill %Missing HP damage, focusing it more directly on destroying beefy targets rather than a squishy nuker. This helps to really resolve between Kog's different builds and roles, which is the main focus of this remade remake.
And that's that! A Kog for everyone. Want a tank-buster? AD is for you. Want your machine gun? Run OnHit. Want an artillery platform? Go AP. With Kog's old Passive gone and his W gaining a significant downside, I suspect that would open up enough kit power to really help this come to life.
Thoughts?