If you cut the wires below the resistors, you will not harm the LED. If you are running a buck puck, I don't see a problem either.
Blue
Excellent. I have ordered my new saber with the quick disconnect, so if the saber has enough room, it should make it even easier. I could just get some matching JST connectors from a hobby store and install a reversed wire between the two parts by simply clicking them together.
The saber is an Archon V2, so the space might be too tight, but a little MHS extender or choke should fix this. For a saber with a longer main body and a longer way from the button to the MLS it could probably be done without adding any extenders.