More, more, more isn't inherently a problem.
It is, cuz infinite growth simply doesn't work, eventually you run into problems
When AoS came out books didn't even have allegiance abilities. Would that be your preference? If not, what would be? Honestly curious.
Things like allegiance abilities, or entirely new mechanics like endless spells, mount traits etc. Are not inherently bad. And you need to introduce some new stuff every so often to keep it fresh if you want a living game.
However, what I miss is hard limits on what any combo is ever allowed to achieve and which may never be crossed, no matter the powercreep. As an example, when AoS started the SCE with their 4+, re-rolling 1's or better on their basic liberators had above average defenses. Now we got OBR with their re-rolling 2+/3+ saves, ressurecting models & a ward save and the SCE are made out of wet tissue paper by comparison. That's some absurd powercreep, even if the point cost is "appropriate", and frankly somewhere along the way someone should've pointed out that maybe things might be getting a bit out of hand.
Another example is spellcasting, where we've gone from casting bonusses being fairly rare, to regularly seeing +3's and now we even have a model with flat out guaranteed casts. How is a basic wizard supposed to compete with that?
Of course I'm not actually expecting GW to outright tell us what these limits are. But with 20+ factions these limits should be fairly well established and we should not be blindsided by a new release suddenly breaking the rules, again. At least not on a regular basis. Breaking core-rules like this should only really happen during big game-wide updates, like going to a new edition. Not when a new faction is released and its randomly 10 times better at mechanic X than all previous factions.
Also, for clarity. A new faction (or unit) breaking these rules does not necesarly result in the new faction becoming dominant. There may be sufficient disadvantages still holding it back from that. However, it does mean that now to keep up, other factions that focus on the mechanic this faction just broke need to be updated to be competitive in this specific aspect. And eventually you end up with silly things, like a regular wizard being useless because all the good wizards run around with +2/+3 casting/unbinding bonusses, which means that your magic is completly shut down for some armies in certain match-ups. Which is just rather weird and kind of lame.
Maybe their "this is too much" line in the sand is simply farther out then yours. Maybe they simply don't always do the best job of balancing a game with hundreds of units, dozens of armies, and a mountain of rules to go along with it.
I'm not expecting perfection, or even for them to put the limit where I'd put it. But as is right now, I barely feel like there is a limit, and at times some of the unbalanced stuff is just so obvious it makes me wonder how they'd miss it.
Regardless, does it matter? Top level tournament players enjoy the chase and the power gaming aspect of it so they are happy. Casual players can simply not use the most broken shit imaginable, and narrative players can pick and choose whats appropriate based on their narrative.
I don't want to have to throw out half the game because it consists of broken stuff. So yeah it does.
And of course currently it's not that extreme. But if you don't put in limits and just let the powercreep grow and grow you'l eventually reach a point where you might as well just rewrite the game from scratch yourself if you decide to not use the broken stuffs. So yeah, it does matter for the more casual & narrative gamer.
Also, obviously it has an effect on the direction the game goes in. If GW decides that the game would be healthier with say, more anti-horde mechanics cuz all the power-gamers are abusing hordes at tournaments this'll change things for the more casual players as well.
Yeah, but how often does that happen? A tiny handful of times? And shouldn't they be doing exactly what you said? They noticed a problem, they fixed it. The realistic alternative is they never fix it or they never even try to create rules that can push the boundaries of the game.
Are we really saying that's a bad thing? I'd rather shoot for the stars and occasionally crash land and need to rebuild the rocket then be satisfied riding horses for the rest of my life.
I don't know how you create dynamic, exciting rules, without also being like "maybe lets pull this back a little bit" every now and then.
I think it happens a bit too often, and at least as important, it frequently seems to be rather obvious that a certain rule is going to be problematic, or the it becomes problematic within weeks. It's not like it takes months for someone to figure out some hidden combo GW overlooked.
The principle is of course fine, design something crazy, test it and dial back if needed. But then your tests do need to catch the flaws before it's released on the general public. And even then, that crazy design should still fall within the basic limits of your game, and that's easy enough to test as those limits should be fairly straightforward (e.g. no better save + re-rolls + ward save combo than failing 1/X times shouldn't exactly be difficult to check).
Also, obviously the fact that they actually fix some of their mistakes is great. They do seem relativly willing to dial back the worst of it at least. Though there do some to be some that go untouched. Admittadly some of those would require proper reworks of relativly new tomes, so it is a decent chunk of work, so you can forgive them for that, to a point.