From one R2 builder to another, I just want to tell you great job so far.
I also want to warn you that while the springs will definitely help with grabbing and wiggling, the thing kids do the most is twist it. They will spin that thing until it twists the wires up and pulls them out of the sockets. I highly recommend adding a mini slip ring to your REON so they can spin to their heart's content without worrying about the wires twisting.
There's a thread on the club forum about it. Search for "holo slip ring". Best couple of hours I've spent on modifications. After 4 events and 4 times repairing the HP, I haven't had to touch it since installing the slip ring.
https://www.youtube.com/watch?v=q4VYiNor4Yk