How do I make my 600 fazer faster?????

[mr self destruct]

Valves open for longer = longer duration, not high lift? Although I imagine lobes would be profiled for a bit of both.

They are. Most standard road going engines are a compromise between torque, power and fuel economy.
If you want to go offroading for example, you'll need an engine cammed for low end torque with high lift and short duration, and a full-on drag race engine will need a high lift, long duration cam that simply will not tick over at anything less than 2k rpm!