Content idea; exotic pets & world
I've always found it a bit upsetting that, bar the frogs you can collect; you can't really have any 'unusual' pets on the Sims. Even having a vivarium or terrarium with the ability to interact similar to hamsters would be better.
My idea would be ideally a full expansion with a new world, maybe something a bit tropical and humid ( including perhaps a cenote, natural swimming areas that are interesting, waterfalls etc.). Perhaps based around the Malaysian Jungles, or South America. I know Sulani has a Jungle, but it's not really a proper, natural Jungle teeming with exotic life.
The ability to keep pets such as birds, reptiles, amphibians and invertebrates would also be amazing, as many folks have exotic pets and I personally feel I can't truly recreate my home in game without the ability to have such things.
It could come with new careers, such as jungle guide, ornothologist, entomologist/arachnologist and herpetologist. This could pair with eco-lifestyle as well as the nature packs, and even realm of magic as you could use them as ingredients for things, such as potions or cures for ailments.
There could be new collections, such as isopods, small spider and lizard collections, also with plants from the new world you can garden / splice, etc.
New Traits could be interesting, such as scared of reptiles / reptile lover, arachnophobia or lover of creepy crawlies, "heart of the jungle" / "fear of the jungle", etc.
It would also be cool to be able to stream with an exotic pet or write manuals / record content about them, as well as having an exotic pets festival included where you can give talks, purchase new exotic pets and get themed t shirts / food as well.