It would be awesome if you added an "if grabbed" to the handle blocks, and i know you dont like adding new blocks so why not just update the current one?
The reason i am requesting the "if grabbed" on/off signal is because i want to make things like van doors and stuff, so they dont slide around when driving, so you can make it lock when you let go of the handle, but you cant do that right now because theres nothing to check if the handles are grabbed, and it would look much better than buttons on doors, please add this feature!