There is a real simple solution to the balance issue...
This gives you a wide platform which negates the need for an extra handle or ANY case mods which may hinder the resale of your housing.
The wide platform also increases the stabilization of the unit by reducing small camera movement.
This is a rather bold statement and deserves comment. Undoubtedly, there are other solutions, perhaps even some involving baling wire and duct tape. To suggest that these are comparable to a methodically planned and developed set of mods is ludicrous.
The tripod mount of the WP-V1 is not very thick and is minimally reinforced. Clearly, it was designed for light duty usage. Anything that extends out from the mount will act as a lever and that could spell disaster.
As for the second handle, the benefits should be obvious: Two hands-two handles. How many u/w video cases have you seen with only one handle?
The Inon DBWP1 mount base does it right by both clamping around the lens mount and attaching to the tripod mount. If you don't mind the considerable added expense and complexity, the Inon mount along with D4 arms and floats looks promising. I bought my camera and case when they first hit the market and could not find any dedicated assessories.
Extra bulk, lights, projections, and extensions may improve underwater stability but complicate entry and exit. If you've ever had to climb a boat ladder in pitching, rolling seas when no one was available to grab your camera, you know what I'm talking about. I just slip a cover over the lens, clip the camera to a D ring, and haul myself out. My camera occasionally bumps the ladder and has not been damaged.
I just returned from Taveuni where I did eleven dives, several with max depths in the 110' range. Everything worked flawlessly. I did no maintenance beyond changing batteries and memory cards. The rings on the lens barrel that I was experimenting with ended up about half full of water by the end of the trip. This reduced their buoyancy by about half but was not noticable since they do not offer much to begin with. I'll be checking into other solutions for these.
I dive because I enjoy it. There is already plenty of gear to contend with. Who wants a fiddly, delicate camera or a heavy, bulky one on top of that? I turn on my camera when something interesting is in sight and turn it off and clip it when not. That's it...That's all... I will never be more than an amateur videographer, and maybe a poor one at that, but I like to capture the adventure of the dive. All my mods were planned with these factors in mind.
You can plan and prepare properly before you hit the water and have a good experience, or attempt to cut corners and suffer the consequences. 
was to Bali, so I'm sure your trip was great.
