TBH living as an animal would probably be terrifying. The human soul/mind is accustomed to a much more refined vehicle, animals are beastly. This is why when Jesus cast the demons out of whoever and forced them into pigs, the pigs went crazy and ran into the water and drowned themselves. But if I could really bear it, I think I would choose to be a house cat, because I'm always curious what their experience is like. Also it seems really easy and peaceful.