Damn those are some expensive controllers. I'm pretty much at budget for this scooter, but those are definitely good candidates for future projects. I really like how compact they are, and modding them per your suggestion would make them killer. I kinda dig that look of both the controllers on my scooter, they get good air flow (not that they're working hard), and they're performing really well.
The grip tape is also another great idea, its worked well for me in the past on my brushless e300. I had something special planned for the new deck and the grip tape would cover it up. After i made the deck I coated it with "the good stuff" and its been doing a good job of protecting the wood. I like your idea of adding weather strip, I may just do that. I want to pain the scooter so it looks nice so I'm just going to weld the extensions on to the frame, the 3/4" strip will give me a bit of extra room for the wiring. I got the scooter stripped down to the wheels which I'll remove before welding. I'm going to stay a little late tomorrow to weld it up at work, then I'll start painting it.
The xlr does have a cover, its pretty sweet how it swivels out of the way when you open it. I'm liking the location of the charger port, its really convenient when charging it up and I don't feel its in my way when I'm riding. I'll post some pics of the welding and painting soon.