Thoughts on Ekko
I am pleasantly entertained with the release of the newest champion to hit the list of league of legends. 
Meant to be an Assassin, i find myself going after low health and/or priority targets. But as a melee champion, i find myself poking abit with my ranged skillshot, then going in to trade/skirmish. As with any champion, there are some champions that you simply cannot fight, but those that he could be able to fight i feel his kit is a bit lackluster. For example, he's all about fighting someone, but struggles vs basically all other assassins(mainly riven, fiora, fizz, leblanc, yasuo). When it comes to assassin vs assassin its usually who bursted/outplayed who. With Ekko, he feels skillful but has to wait for AI to get the things he needs to trade effectively. That to me is the only downside about Ekko. I feel as though i would be more confident at attempting to trade with other melee champions if Ekko was capable of getting his shield as soon as he steps into his W, opposed to waiting for the holographic version of himself to hit a ball inside. Although that should be the stun, when the ball hits the target location with Ekko and champion X inside. I find myself attempting to trade with some fighters/assassins and often losing the trades unless i whittled them down with his Q. Assassins deal insane bursties and Ekko is one of those champions who will probably have all kinds of item paths. But going in to trade with some champions, i find myself low health at the end of the skirmish. Due to me trying to stay inside the w for the shield proc, but having to wait for the AI to hit inside, i find myself out traded in the time it took to wait for a shield. So when i finally get the shield i'm haunted by the idea "do i decide to trade now even though I'm behind on health but now i have this shield?" Also if the enemy champion decided not to stand within the W for the stun then i find myself so low i cant wait 2 extra seconds for my ult to make it to me for that burst. I wind up having to use it for the heal and back away. Which essentially is his kit, seeing if you can outplay someone within the time given, if your winning and got the stun off then another 2 seconds the ult should finish them off when timed correctly, if not then you ult to safety.
TL;DR Basically skirmishing on Ekko may not always be worth the risk, since it can take a few seconds to proc his shield. I had the idea he would be much more effective at fighting someone if the shield proc'd as soon as he enters his W, opposing to waiting those split seconds for AI to set up a shield combo. Another idea of mine was to increase the speed at which the ball travels to the target location. But is that part of his counter play, being able to DPS him in the short seconds leading up to his shield/stun burst?