The visual design seemed really messy because you'd get all these dudes fighting and they just kinda looked samey so it would be a mess of characters that looked the same. Like I found it really hard to pick out heroes when they were fighting right up against creeps.
I mean... no? The only 2 characters that are even that similar are Oscar Mike and Wikey Foxtrot. Otherwise, silhouettes, animations, and effects are very different between almost every character.
And I play constantly on Splitscreen with my brother online, so my screen is usually even SMALLER than usual, and I still never had issues picking characters out. I had more issues picking out characters in Gears of War, since there's little to no silhouette or action difference between Locust and Humans.
The biggest misstep I think they have is that there's no colored outline around characters, and no "team colors", since people are free to pic their own costumes and such. There are team outlines around AOE effects and such, but when you first start the game, you'll die to the ability before you know who hit you with it.
This all disappears, and becomes a non-issues as you learn the game's own language. I haven't had issues in weeks.
Also, the abilities didn't really give any feedback on what they were doing. Nothing felt like it was really doing anything and it was really hard to tell what it was even supposed to do without reading the wall of text descriptions.
Game just didn't feel good to play.
This also untrue. There is a little "tick" sound that happens every time an ability/shot of yours hits, and of course, you see damage numbers ticking off enemies, and feel controller vibration. Not to mention enemies moan and groan when attacked. Some of them are oddly non-sequitur (such as Mellka's poison effect sounds like you're getting shocked when you take the effect), and it's not the same as many other games (screen flashes or blurring effects are different), but again, it just has it's own language for how it handles things.
Not all games feel good to everyone, but I found it pretty easily to acclimate to personally. It just actually required adjustment, as opposed to other games which just feel like reskins of another series sound effects, screen effects, and movement / attack timings. If anything, that's what drew me to it; I love the fact that Melee felt like honest to goodness FP melee, rather than a tacked-on bonus to shooting. Gun assassins and sword assassins feel unique! And actually different from other gun and melee classes. Shields are actual HP, and some characters don't even have them, or have physical ones. Characters even have dash attacks, varied melee, and "quick melee" actually serves a purpose (pushback), even on gunners.
It's got gameplay depth that a game with 25 play styles to balance shouldn't have pulled off so well on first blush. But you'll never appreciate that stuff, if you're turned off early on, which, as a person who enjoys the game, I find that quite unfortunate. Especially being able to play it all solidly online in splitscreen, pushes this game so far past others in personal fun-factor. I haven't had comparable fun + online since Awesomenauts original release, or Monday Night Combat on 360.