The thing is, there is a LOT of pet collectors on wiz, and it's impossible to store all of your pets, where they can walk freely, in, or outside the house. It would just be so cool to have a own pet castle, or a pet island! Where there was a "no limit" of how many pets you could have there. I myself is a collector, and it's hundreds of different pets in the game, and I would like to hatch them all! And I know I'm not the only one, this would be amazing to have!
You can have a pet island sort of. You can build it with blocks and make a pet world. It's a crown only house and I had a ton of fun with it. Use that if your heart desires more flexibility.
This is a cute idea! Though, maybe instead of a crown shop only house, make a pet vault of sorts! For one, I think making it a crown shop only thing would be a terrible idea. ALL pets can be gotten with gold one way or another. Someone will have paid the crowns to get the pack or bought the bundle and they will want to hatch with others to make that pet better. Why force those who don't want to spend their crowns on something like this to do so when any pet can be gotten for gold alone, eventually.
They could made a craftable teleporter item, like the gear fault/seed vault/jewel vault that would teleport you to a small pet island. It would be like a small house, one you could decorate and all, but it would be a place mainly for pets! Maybe reverse the restrictions so you could have 250 pets and only 50 of those being furniture items.
Maybe they could have special pet training games you could play with your pet when you go there that you could make/farm/buy to add to your pet house. Maybe add special emotes to the house so you could have you pets all do something at once and what not. Make them feel more then a just a piece of gear or a fancy decoration for your house.
This might solve the problem of needing new pet training games and allow for pet collectors to have more space for their beloved pets. And, I would imagine, if it was like a gear vault, you could have one inside and one outside so 2 pet houses per house! That would certainly solve the problem I think. Even with a 250 limit. Maybe make the limit upgradable with a brik-a-brac elixir like a regular house.