This game is the best, and it definitely has a lot of potential as an idle virtual pet game! I've got some suggestions and ideas for the next update, if you don't mind -I've read the comments so I'll try not to repeat things that have already been said.
* Ways of increasing the amount of money you get -it takes a while to make money for the extra expensive stuff and gets kind of grindy, which isn't much of an issue now because there aren't many items, but it could be annoying in the future if more items were added.
* More decorations/furniture items -There ain't much to do decoration wise, it's a great start and it could become one of the best parts of the game if there were more items as that's currently the only real goal the game has.
* More kinds of collars/accessories for adopted cats!
* More to do with windows -Cats should seek out sunbeams and sleep in them, and they should also look out windows. And windowsills that they can jump on
* Recurring rare cats -What if there were recurring NOT randomly generated rare cats that had unique sprites, that caused things to happen when they were present, and had unique conditions for their appearance?
* There definitely needs to be more to do with the outside yard. 90% of the items in the game are designed to be used indoors.
* Random events that affect cat behavior -for instance, all cats in the yard rush inside when it rains
And finally, this has been said before but more goals need to be in place. What that looks like is up to you but I do think this game has potential and you're off to a great start overall