Thanks for the question, I’m always happy to help!
You could write a script that tracks and tags nearby objects with the TimeScaleWhitelist tag. Other than doing that I’m not sure on any other way of doing it with this framework.
I can consider this for the future and have thought about it in the past there’s just some other parts of the framework I’d like to work on before coming around to these sorts of nice to haves. 
Really love this creation. For the humanoid jump, I think what if you was to alter the humanoid’s jump power and/or also create a loop for when they jump, it’ll slow down their character’s velocity? Just throwing an idea out there.
(And also, apologies for the random bump of this post)
I’ve given a few different ways a go, I think the ones you listed there too for slowing down the jumping of humanoids accurately but none of them have quite done it properly. If you’re able to work out a method for it then you’re welcome to contribute on the GitHub.
I would like to get the small issues like the one you raised solved with this project but I’m not sure on how to go about it so if you know anyone else that might be able to help out with it be sure to ask them too if they can help!