A good tool kit should allow you to:
Remove and replace the battery.
Remove or install either wheel. (FZ6 kit fails here, it won't do the front wheel)
Drain and replace all the fluids.
Replace any burned out light bulb.
Adjust the suspension.
That's the basics. You can add to the toolkit to add the following abilities. My touring toolkit had all of this stuff.
Test an electrical fault.
Solder a replacement wire into place.
Transfer fuel to another bike.
Repair a punctured tire.
Inflate a low tire.
To accomplish all of that, I added the following items.
Butane soldering torch from Radio Shack.
12" of rosin core solder
several lengths of wire
$10 Radio Shack multimeter
Mag-Light
Stop and Go tire plug kit
Electric air pump. When you remove the plastic case from one of these, it's surprisingly small.
Several feet of fuel line.
Replacement fuses.
Heat-shrink tubing. (This probably won't work on the FZ6, it'll get so hot from the exhaust that it'll shrink the first time you go for a ride.)
The key to a bike's toolkit is that you decide what problems you are willing to tackle while on the road. You attempt each one at home, and work out what tools are needed. Those tools are put in the toolkit. For all other problems, the cellphone and credit card should suffice.
Fred