I've finally played all the modules in Kittens + Beasts.
Kittens - A good addition that add incentive to be first
Beasts - I found this to be kinda meh. I didn't like that you can only get beasts on the first day which makes it really easy to just skip the whole module.
Events - I really enjoyed this module. The events really add additional layers of strategy and time sensitive ways to score points.
I just got the Kittens + Beasts Expansion for Isle of Cats and played the Kitten module. The small size of the kittens and being able to rescue two for one basket makes it easier to fill out those smaller spaces that used to require treasures. It definitely adds incentive to be first for the round.