I want to suggest a feature where you can change a pet's birthday to a specified date.
I have a pet named after my precious person and I really want it to have the same birthday as them, so I figured that having this feature will make a lot others happy as well.
Personally, the reason I don't really engage with Tatsugotchi is because I can't be bothered to take care of them and would rather they not run away due to my negligence.
I would find it interesting if I could purchase a "Sitter Subscription." Basically, your credits would be charged on a recurring basis to keep sitters topped up.