FUCK IT. I am a Zed main. I see you have an issue with my champ. More specifically, an issue with my champs Q, W, and R.
So basically if I am understand what you're throwing down you hate Zed's Q because it goes through multiple targets and thats too op. His Q has a SEVERE restriction on it if you do not hit a champion as the first target. In fact, ITS A 40% DAMAGE REDUCTION BEFORE ARMOR IS APPLIED sort of restriction. His Q is perfectly fine since its got a built in mechanic that punishes Zed if he does not hit a champ with it first. I don't really think more needs to be said about his Q other than this: if Zed's Q could only hit two targets like Veigar's Q it would probably hit like a fuckign truck since it would have to be hugely damaging in order for Zed to not be completely useless since he is melee and his Q is his only ranged ability. IMHO we are all better off that Zed's Q is the way it is now rather than dealing nearly double the damage it currently does but only to two targets.
Next up is Zed's W, which you said "an escape, gap closer, a spike in his harass" and makes him the safest assassin you've ever seen. On the first note you are totally correct. Zed's W is all of those things, BUT ITS NOT ALL THOSE THINGS AT ONCE. Zed's W is probably his most LIMITING ability right now. It has an insanely high cooldown at 22 SECONDS rank 1 tho it does go down to 14 seconds at rank 5. In fact, Zed's W is one of the highest cooldown mobility spells in the game rivaled only by Azir's E and Zac's E in length at ranks 1-5. HOWEVER, unlike most assassins Zed does not have the luxury of maxing his W first, hell he DOESN'T EVEN MAX IT SECOND, which means that champs like LB and Fizz get to have lower cooldowns on their escapes sooner and in terms of mobility spells Zed is the only champ I can think of who is forced to max his mobility spell last. Hell even fucking Maokai gets to max his W second. Also, the fact Zed's W is so overloaded is precisely the reason why it is balanced. I know that sounds crazy but hear me out. Because of the fact that Zed's W can do so many useful things means that Zed cannot use his W willy nilly. He is forced to choose between using it to poke, using its mobility to engage, or using its mobility to disengage. This fact is doubly hammered home by the high cooldown of the ability making Zed incredibly vulnerable for the duration the ability is on cooldown and also hugely punishing Zed for incorrectly using his W. In fact, 9/10 times that I die on Zed is because I misused my W or did not play safe enough during its really long cooldown. As for your second complaint about Zed's W making him the safest assassin ever, I just have to ask you "Have you played vs a LB or Fizz recently or even an Azir?" Both Fizz and LB not only get to max their escapes and gapclosers first but all three champs also have much easier ways to get cdr than Zed does. In fact, Zed needs 2200 gold to get merely 10% cdr (technically warhammer is 1100 but buying a warhammer first item is very suboptimal for damage thus you need to purchase both parts of Youmuus to gain its 10% cdr) which is double that of Fizz, LB, and Azir. Also, to get 40% cdr Fizz, LB, and Azir need around 7k gold, whereas Zed needs around 8-9k gold to get 40%.
Finally, we come to your complaints about Zed's ult being too safe because it allows Zed to not only gap close onto a target but also escape from that target after he unloads his damage. It is true that Zed can escape quickly from a target after he ults them BUT there is a delay of .5 seconds. That may not sound like much but this game can be determined by tenths of a second and a skilled player will absolutely take advantage of this delay as will decent teammates. Also, nearly 80% of the time Zed must first use his W to get in range to use his R and his R only has a range of 550, which is the basic attack range of most adcs/mages. This means that Zed's port back is quite short and once he does port back he doesn't have his W for around another 8-15 seconds afterwards. Also Zed's W/R shadow makes it clear where he is going to port back to making it easy to pick him up with cc after he ported and for the most part Zed will still be in auto attack range/spell range of most targets. And to be quite frank, while adcs no longer have qss to remove zeds ult they still have a fair amount of counterplay to him. In fact, adcs can buy GA, get peeled by a support with exh, use heal, use flash, have Zed peeled off by another teammate, or just str8 up murder Zed when he gets on top of them. Remember, Zed is still a squishy champ and later on in the game when adcs have a lot of ad and crit all it takes is 2-4 shots to either make Zed have to port back before he can deal lethal damage or just str8 kill him. And if Zed ports back before he can deal lethal damage he is still within the range of most adcs without his w up which means hes basically dead. Also, (in response to your comparison of Zed to other assassins that cannot escape when they all in) may I introduce you to LB who's R and W give her 4 teleportations and a passive that lets her become invis for a full second to reposition. Or Fizz who has a very low cooldown on an invulnerable gap closer that can be used once to get into a fight and delete a target and then used again after only 4 seconds to escape from said target(lets not even mention his fucking 700 range dash Q). Or Talon who cannot escape but is compensated for this fact by not only having low counterplay to his damage as it is nearly instantaneous but also by his damage being AOE and can hit multiple targets quickly. Or Akali who, much the same as Talon can't really escape, but is compensated for by having multiple long range dashes giving her high sticking potential and high single target uncounterable damage (not even going to mention her W that lets her go invis, gives her movespeed, and slows her enemies). Or Azir whos zoning powers are the best in this game with a game changing ult. No unfortunately Zed's R is not nearly as broken as you might think since he trades instant uncounterable damage and AOE damage for high single target DELAYED damage and an escape.
And for my last point, to be brutally honest I think that the qss changes are the biggest nerf to ever happen to Zed. He got hit with the ultimate nerf: A FUCKING 90% BANRATE. #FreeZed