I think you're on to something. Since hull speed isn't an issue for a boat that spends most of its time upside-down, I recommend welding a 5/8" thick slab of HDPE with helicoil screw inserts over the places where you've already drilled into your hull. This way you can patch the holes and install an awesome camera mount at the same time. The camera should certainly go on the front to get some great footy of your chunderings down long stretches of Class IV and V as your boat follows you down the river. This will also give your lame-ass buddies more incentive to paddle hard enough to catch up and rescue you just in the nick of time before going into a nasty sieve / strainer / waterfall. Who would miss a chance to get some prime video to put up on the internet that shows everyone how badass and
heroic they are?
And as you've already got a set of holes under your seat you need to patch over, you could put another HDPE slab with helicoil inserts under your ass and mount your waterproof river stereo speakers
to the bottom of the boat. This way you can have the obligatory heavy-metal soundtrack for your near-death beatdowns. Choosing the right music for your misadventures will be critical - If you're planning on a marathon recirc, you'll want something like Spinal Tap's "Hell Hole" whereas for a mile-long swim down a boulder choked creek AC/DC's "Highway to Hell" would be more appropriate. Since Top-40 format limits a lot of tunes to only 2 or 3 minutes, you'll want to use the "repeat" function so that perfect song keeps playing for your entire swim.
The speaker may also be key to your survival as it'll provide energetic background music to keep your buddies fired up while they're doing CPR (Pro tip - you should also put "Taps" in your waterproof i-Pod's playlist just in case they're not successful - having the right music will be crucial for your friends to post up a really touching video on FaceBook for your elderly relatives to remember you by).
I just want to say its really inspirational to see someone making the most of the off-season the way you are. Your prior planning will provide excellent entertainment and cautionary tales for the rest of us. If only more folks were as thoughtful and considerate as you we'd have plenty of good boating video to enjoy until the flows come back up. Just remember - before getting on the water make sure your friends commit to posting up the rescue stories and swim / rescue video in case you don't regain use of your hands until fall!