Tardigrades are near indestructible! 😀
Yep, many different possibilities that definitely need consideration. Take Venus, for instance. There are some theories that microbial life could be living in its clouds. Fortunately, this is a planned mission but by a private party. We need more publicly funded missions to keep the private sectors from laying exclusive claim to any findings but I digress.
This could very well be extended to stars and gas giants, as you mentioned. In Skyward Sword, we had this lovely fellow. May sound a bit farfetched but it’s quite possible! Who knows what lies beyond our understanding?