I think teemo shoudl be reworked into an assassin
HERE ME OUT BEFORE YOU START HATING!
First of all lets address the fact that his kit is fairly meh these days, his shrooms have been gutted several times, cutting the damage, and now the legnth in which they remain, making them a very weak defensive option overall. I dont think they shoudl be removed, but they dont do as much as they used to anymore. His Q does a fair amoutn of damage, but thats about it. Ive already made a post abotu this, but blidns are useless, every single champion in the game has a way to compeltley ignore them simply by using an ability, and even some champions who do rely very heavily on autos like vayne or nasus can still hit by pressing a button and autoing (try it, if vayne tumbles her next auto, even if blinded WILL HIT YOU). His W, while neat, only offers a short term escape that gets disabled with a slow, or any amoutn of damage form anything. And his E is pretty emberessing these days, build visage and now you never take damage again.
So, i think teemo shoudl be reworked into an assassin style champ, hes already pretty clsoe to this as is if you build torment and echo on him.
So first, his passive should be a bit buffed, the auto scaling is fine, the invibility is fine, but what if he woudl be granted 1 second of invisbility once he moved? Or leaves a bush? And to ensure teemo doesnt go invisible, move for 1 second, stop, move for 1 second, etc. You put his passive on a very short CD, maybe 3-5 seconds so he cant jsut run into a bush, go insivible, W and rush to the next bush and hide again. this would allow him to move aroudn the map relatively smoothly.
Next, his Q could be reworked every so slightly to be more like graves smokescreen, same damage, more or less the same effect, but it massivly reduces vision, allowing him to chase or kite better, as well his Q should apply on hit effects, like shyv, or his own E. I mean come on, are you telling me he doesnt tip his blinding dart with the same poison he uses on ALL OF HIS OTHER DARTS?
His W is fine i guess, i cant think of a fair way to turn this into an assassination tool, other then maybe jsut removing its mana cost.
His E should also get a slight buff, maybe it scales with AD as well as AP? Maybe it procs on hit effects? like torment or soemthing? i feel like that MIGHT be going too far, but given how weak he is overall, and how easy it is to ignore this damage maybe its not so bad.
and then of course his imfamous shrooms... I think the ideal balance is to up the damage, not by a lot, but by a small amount, increasing over time. As well as increasing how long they stay in play based on level, so they start at 5 mins, then 7.5 mins at lvl 2, then a full 10 at lvl 3. And then, instead of jsut going out by flopping over, they should explode on their own apon their deaths when they run out of time, sure this wouldnt do much, other then let the enemy know "Hey, i was here 5 minutes ago" But some teamfights you try and lure them through shrooms near death and they jsut BARELY miss them, so now if you kite and they somehow manage to miss every shroom near death, maybe, JSUT MAYBE they stand next to one that blows up on its own. this would also be useful for misplaced shrooms, which can happen sometimes when you are throwwing them out in a hurry, or are about to recall and have jsut enough mana for one shroom, its in rnage of soemthing, but its hitbox is jsut small enough that is misses, wlel now in 5 minutes that something might actually get hit.
Now i realise everyones going to jsut ignore this, downvote it, whatever. But be real, take a step back. Teemo right now offers NOTHING to his team. He used to be strong enough to counetr garen and nasus, but now they jsut play passivly, taking jsut enough farm for visage, and then you are useless. You can do a thing. Sure you can give your life to blidn the ADC, but as stated, blinding peopel does almost nothing these days.