One of the Hundreds of Rework ideas that get posted on the forums, featuring Aatrox
So I'll skip the part about probably being ignored since I cleverly (not) wove it into the title and get into the meat and potatoes.
I'm going to try to be fairly short and sweet since I don't think Aatrox needs a ground-up rework, just an actual Ultimate, a less weird E, and a W that isn't.... the most boring ability ever (see Xin, Vayne.... and every other 3rd auto proc champion ever). That said I do love the idea of Aatrox, he's a lot like a melee Vlad, and I feel like a hypersustain melee version of Vlad has some very interesting implications on the game, and a healthy role in the game. It's more or less the execution that's flawed at this point, which I can understand. The thing I feel Aatrox suffers from most is being a jack-of-all-trades. You can build him glass-cannon, tank, and bruiser, it's all really relative as to what your team needs. This is a pretty impressive strength a lot of people tend to take for granted, but it's more the "well why wouldn't i just pick X instead?" dilemma as you feel more and more frustrated by your lack of success even when you have an absolutely wonderful laning phase. All that said, I think just saying screw it and letting Aatrox be Aatrox is the best course of action.
Passive- Blood Well
I know I said only his W and Ult, but I lied. I think adding a scaling global damage vamp (not just life-steal or spell-vamp) onto his passive wouldn't be too terribly amiss. Hell, replace his attack speed steroid with it instead. Aatrox should feel like a bonafide murder machine, and while attack speed is a cool stat.... it's hardly the most original. I think doubling-down on his sustain is a much better way of emphasizing his play-style. It forces enemies to chose between bursting him or other high-priority targets on his team. It also incentivizes him building tank, because if he can survive the burst then he can use the downtime between the bursts to help him re-enter the fight and really get to making war.
W - Lacerate
So full rework on this particular ability. Not that I didn't like the old infinite sustain w, but I feel like having an ability with interaction is a lot better for him in the long run. So the general rundown is this, AA reset that expends a portion of your Blood Well as bonus damage as a DoT. Reasoning being is that no matter how you look at it, Aatrox is always going to be AA based, and as such not having an AA reset puts him severely behind when trying to trade with other fighters unless he has something fairly drastic to tip the scales, such as Trynd's crit passive, or Irelia's "Time to win the trade" button. I think it would be interesting to add the trade-off of dealing damage at the expense of your Blood Well, which would put you in a less secure position for extra aggression. I think a DoT would be more fitting Aatrox's playstyle since he's most certainly more of a sustained damage dealer, and high scaling burst would just feel wrong.
E - Impale
Again another full rework on an ability. Bear with me through all of this, I know I'm probably overkilling it a bit, but I'm feeling inspired so please indulge me. Anyways on to the ability, Aatrox's current E is just kind of... funky. It's a bit of an odd fit with his kit considering it's a really weird warlock-esque power coming from a bloodthirsty war devil. All that aside, I feel a slight mechanic and animation change would help make it a good fit. Rather than casting the fairly odd skillshot that comes out, I think a Jarvan-like line-shot would be a bit more appropriate, Trading the slow out for an armor shred, and having total AD scaling instead of bonus AD.
R - Massacre
So here's where things get.... fun. I really want Aatrox's ult to live up to its name, and I think I have a fairly interesting way to do that. We have a bunch of "fun" kite champions in league now. We all love trying to fight Kalista, or Nidalee, or Ahri, or Riven, or Lux, or just damn everyone you can't catch up to no matter how many summoners or CC immune ults you got (life's tough ain't it Olaf?), which stands to reason it's a bit confusing why there isn't an anti-kite champion... Which is a role I think Aatrox could fill. Shaving off the extremely annoying aspects of a kite champion, no slow on his E and having a longer cast animation on it just for the basics, I think it's not only possible for Aatrox to have a unique role as the go-to backline diver, but it's also kind of an intuitive design choice for Aatrox. Now moving onto the crazy bit for Aatrox's ult.
Tl:Dr, it's still a steroid, but instead of being an AS steroid, it's now his tool for hunting down the enemy, turning his abilities into tools of war, and punishing him for fleeing battle. While Massacre is active, Aatrox's Q recieves a substaintially decreased cast time, and a large portion of the CD is refunded on successfully damaging an enemy champion. In addition, Lacerate no longer consumes Blood Well on being cast, and auto-attacks reduce the cooldown of the ability. Impale will also pull Aatrox to enemies that are bleeding while Massacre is active.
So as a final comment on my vision for his ultimate, I understand full well that it's probably a bit much, but at the same time I think that Kalista being impossible to catch, or Vayne being impossible to get away from is also a bit much. My frustration with this is that there's no real way to counter these kiting playstyles other than having a ridiculous amount of CC, or one hell of a wombo-combo. In addition, all of Aatrox's newer abilities are designed to better get him into the fray, but not necessarily get you out. Similarly you are punished for not connecting properly to your targets, and a good peel from say Janna, Leona, or Braum is more than enough to keep your precious waifu Ahri alive.
In summation, I think that doubling down on Aatrox's ability to sustain, and giving him the tools to really start bringing war to his foes is much more preferable to the more boring AA-based bruiser pattern. Turning Aatrox into a guided missile to take out the targets no one can seem to keep up with puts him into a bit of a unique category as a fighter. There are plenty of assassins with delete buttons, but it's always the rage-inducing moment for a fighter to never have the ability to keep up with someone long enough to actually fight them.... it's what they do after all. Anyways thanks for anyone taking the time to read all this, I hope I broke up the text enough so it's not too much of a wall of text.