Mostly VVEL is a fuel-efficiency hack, IMHO. The problem with a solid cam is you can either profile it for good torque, or profile it for good MPG, but it's kinda hard to get both. VVEL lets them meet the MPG standards that the feds and/or consumers want and still deliver power when you get on the throttle.
The VQ37 is pretty decent on torque given it's a 3.7L V6, but it likes to be in the upper rev range. I know most people in normal conversation talk about "torque" as being the low-RPM stuff and HP as the high-RPM stuff, but HP is just Torque*RPM. You can't have good power output in general without first having decent torque somewhere in the rev range
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