水草子 Thank you for taking the time to give us your feedback! We have received requests from several users about baking and looping animations created with physics constraints, and we are considering some of them. You may be interested in the following thread:
https://esotericsoftware.com/forum/d/25169-baking-physics-and-looping/
We have a lot of features and improvements we want to add besides the physics, so it may be some time before we can respond directly to your feedback, but thanks to you for posting your opinion here, we will be able to take your input into consideration when we look at improving the physics again.
If you have any other concerns or suggestions, please feel free to post them in this forum. Thanks again!