I am going through similar probs with my Rocket. It is very difficult tweaking the maps without knowing any CO readings. The Innovate wideband would be the way to go however to gain the greatest benefit you would need to datalog with the Tuneboy datalogging program. That requires carting a laptop with you and leaving the Tuneboy cable connected to the bike.
The Keihin ECUs use a narrowband O2. If you look at the a/f map only the areas that have an a/f target of 14.57 to 14.7 cause the ECU to go into closed loop (use the O2 sensor). About the only time they go into closed loop is idle and small throttle openings. So you could change the a/f values to 14.0 (which would cause the ECU to stay in open loop) and disconnect the narrowband stock O2 sensor and plug in your wideband do your datalogging and replace the stock sensor.
Another option have another bung welded onto the exhaust and plug in a wideband sensor when you want to datalog and not have to worry about messing with the stock setup and connections to the computer.
I think your money would be better spent on a dyno session or two to obtain a good tune. Another problem is that wideband sensor setups don't have as long of a life on a motorcycle.
One benefit of Tuneboy is that you do about anything Triumph can do with its datatool and you can make ignition mapping changes also. I have found most of Triumph's stock tunes really suck.
Some wideband links
http://www.widebandcommander.com/
http://www.wbo2.com/
http://www.innovatemotorsports.com/products.php