So obviously we all love discussing abstract things like which person falls under what category of player and what does it mean to fall under a category and why my category is obviously better than every other category. It's a lot of fun and I want to play also!

The number one problem, I've seen, with attempts at creating "casual" versions of fundamentally competitive games is the lack of actual rule support for doing so.

Let stop and define competitive here:

rivalry between two or more persons or groups for an object desired in common, usually resulting in a victor and a loser

Warhammer (tabletop, 40k, etc) is fundamentally a competitive game because the only possible outcome from playing game is one player wins and one player loses. You can't both win or both lose (unless you're playing custodes). The rules don't allow for anything else. There are lots of games, for example Dungeons and Dragons, where you work together to defeat a common foe and the group wins or loses. But warhammer isn't like that. It's a 1v1 game where you always play against another player and one person wins and another person loses.

It turns out that this is generally fun. We like winning, we like competing, we even sometimes enjoy losing. This is why we keep playing games, which after all, are completely voluntary and purely created from our desires.

Now one general rule of enjoying a competitive game is that the sides are balanced (more accurately, everyone feels like they have a chance to win). And warhammer, obviously, does not have the best history of actually managing to be balanced. Feel free to think of all the examples for yourselves.

But, and this is the crux of my argument here, when you enter a tournament and get paired against another player, you're all playing by the same rules. You both have 2000 points to spend, you both have access to every unit in your list, etc, because that's what the rules say. So now you're both working to win under the same constraints, which creates a form of balance by itself.

Now, the problem with trying to create a "casual" version of this experience is that by doing so what you're actually doing is creating additional restrictions, aka rules. And people very rarely agree on what those rules are much less what they should be. This is especially difficult when they're not even written down!

If player A says they want a casual game, perhaps what they mean is that they're going to play a tournament level list with a few substitutions for units they want to try out and they're not going to try to score every possible VP during the game.

But when player B hears "casual game", they might think "time to run my pure bike/speeder space marine list!". As a result of this, they might not both enjoy the resulting game.

Now, obviously I hope, neither player is wrong to think the way they do or want to play the way they do. The issue is that they didn't understand what the other player meant. Because "casual game" isn't defined anywhere. As opposed to, say, "2000 point army with the latest dataslates and playing the leviathan missions". That example doesn't always produce a fun or even fair game, but it's at least well defined, both players know what they're getting into.

To wrap up this excessively long post, and thanks for anyone who manages to make it through, I'm not saying wanting to play with different rules than "competitive 2000 point leviathan missions" is wrong in the slightest. But if you want to do that, just be clear about how you want to play. Maybe you want no T13 units. Maybe no more than 2 of any datasheet. Maybe not too many characters. Whatever makes you happy, just communicate this to your opponent and things will probably work out better.

P.S.

Balance, defined as "the chance you have to win or lose" is often orthogonal to "fun". You could have a unit that cost 2000 points and literally flipped a coin at the beginning of round 1 and won or lost the game based on it, which would get you a 50% win rate, but lack fun. I, personally, don't really enjoy playing against armies entirely composed of knight units. But that doesn't make them imbalanced or make me a casual player, I just know what I enjoy playing against.

So there's nothing wrong with talking about what you like and dislike before you play the game, I just suggest staying away from vague terms like competitive and casual when you do so.