@Meat Grinder. That was 3 Panthers, 1 Tiger I, 1 Tiger II from my count.
@Herroberst63 I fully agree with your assessment about percentage limitations on armor giving an advantage to the German side (in almost all situations). One strategy for helping to overcome the superiority of German armor is to outnumber it. That also comes with a risk, as any force weighted too heavy in one direction will be disadvantaged, as
@A Canadian Cat stated. I think the player, not the opponent, should be responsible for their force selection, and the resulting outcome.
The one rule I can see some good in is where the German player has to buy one other fully tracked vehicle, before buying a Tiger/Panther. I understand the frustration of some as to how QB's can become just a destroy the Panther/Tiger fight. I have seen Panthers/Tigers take ungodly number of hits and still be able to function seemingly unaffected. (Meat Grinders King Tiger mentioned above has taken about 40+ hits in my count, immobilized but still able to pick off infantry teams easily at 800+ meters as it is being hit itself. So no negative effect to optics, weapons, crew morale, etc it seems

) The Panthers 0 rarity in purchase makes it a cheap dominant machine. All that being said I think I have only used that rule maybe 2 or 3 times (at others suggestion) in all the games I have played. I find one of the weaknesses of Tigers/Panthers to be that they are many times used as if they are invincible, which they are not.
The only agreement/rule I always put in is my: "No pre-planned arty/air from the defender, and defender will not purposefully target/engage troops in the attackers setup area. Attackers units will leave the setup area before engaging." A good map will render most of that agreement moot, but I find it simple, effective, and not a burden. Gladly abiding by it from either side. I am sure not everyone agrees with that, and that's fine. It's just my way of keeping a good attack/defense game from becoming a meeting engagement mess against the map edge. Not trying to start another discussion on this, or hijack this topic, just merely stating my view.
All that being said I think it's sometimes fun to agree to infantry only games, or games in which medium/heavy armor is not used at all. But that's always with someone else who is eager to play in such a way. And other than the overall "we will buy none of these" agreement, there is no restriction on how or what each person can buy with their allotment of points.
I have played games in which my opponent makes a purchase, or makes moves in a way I think is taking advantage of the games limitations (or lack there of) and knowing it is not a force purchase or move I would make or enjoy. But I have never wanted to make long lists or rules, restrictions, etc because I feel it's just adding limitations based on anecdotal experiences and does not lead to any better game play. I know not everyone who makes long rule lists does it for their advantage, but there are also those who do. I like having the game and players decisions "shape the battlefield" as Canadian Cat put it.