I'd love a comp mode without rank. I really think when I hate the game the most is in competitive. Too many people are focused on SR and the constant argueing over what to play.
The games modes are good, but each of them are flawed in a different way for me.
Comp has the best game set up by FAR, but the ranking is an exercise in frustration to watch. Like, I actually don't look forward to moving too high up because the more I progress, the more intense it will be. But I don't want to level down either, that's just discouraging. So do I have a casual option? Not really.
Brawl doesn't track any stats and I think that's a great thing, but whether the game is good depends on the week. Most of the game modes are joke modes that can be fun for a few minutes, then you realize the game is just fundamentally broken. "What would the game be like if we only played tanks?!" Well, a lot less interesting because you remove all the differing characters and probably broken because the game was designed to function with those other characters, is what. I like Mobawatch the most since it comes closest to replicating Comp without ranking, and I love Junkenstein as a co-op game, but that's it and it only appeared a few times since the game launched. Junkenstein's revenge is currently awesome, but most of the time, Brawl is stupid.
Quickplay can be either casual fun or more hellish than Comp. If both teams have diverse team picks and are trying to win, it's great! But herostacking sucks and is the worst piece of the game by far, and I wish Blizzard would get it through their heads that no one likes it. Plus, team comp is always going to be a dice toss. It's not even that your teammates necessarily suck, but if one guy wants to practice his Widowmaker, well, the only place he can do without being punished for it is QP if the Brawl doesn't allow for her (it usually doesn't). So there are several players who are flat out not even interested in winning the game.
So the way I see it, Blizzard would do well to set up
1. A practice mode that basically functions like QP does now. No stats are tracked and the explicit goal of the mode is not to win, but to just play with whatever characters you want for casual fun that has no lasting consequences on your W/L ratio, so you can do literally anything you want.
2. A new QP that limits hero selection. With #1 existing, people will have the explicit purpose to win, not fuck around with characters, and we won't get hero stacks that no one likes. Simple.
3. A solo-comp mode that ensures that people can't be in groups. This way, people can play with Ranked rules without having to worry about being matched up against a team.
4. A Co-op mode like Junkenstein's Revenge that incorperates more/all characters. This is probably the biggest thing to ask for, because they'll need to develop a lot of enemy AI's that wouldn't just be completely wiped by certain ults. But I love Junkenstein's revenge so much, it'd be so much fun to have a way to Co-op this game against hords of Omnics.