Did you consider mounting the coax end in the plastic somewhere rather than under seat?
Like maybe just below the left pocket door.
I did not consider that. Seems like a good idea if a panel mount type jack is available. I do have the Honda heated grips and their controller is mounted in that particular spot. Make sure the lead coming out of your heated gear is long enough to reach.
I've left the setup the same for the 3+ years since the install and it's worked just fine for my needs. During the hot summer months I can just tuck the lead away and forget about it. During the cooler, heavier usage months, it tucks in nice and stays out of the way at the bottom edge of the seat in the indent formed in the plastic for the seat. Never a problem and gives pretty good freedom of movement, with the cable extended, when I am plugged in.
Show us the pics if you panel mount yours.