What I propose is splitting the Variable Valve lift option between different tiers to represent the difference between the aggressive cam range possible with a multiple-cam system like Honda’s VTEC versus the more limiting ranges granted by the simpler option of shifting the camshaft used by other manufacturers.
The milder of the options would be more cost-effective and cheaper to design, but would only allow a maximum of 10-20 units over the regular cam profile; in contrast the more aggressive system would allow full range of the cam profile at the cost of much more investment in design and research. This would also be an good option for research upfront/exclusivity if you implement such a feature in the R&D system.
Another option would be to increase the cost of the VVL option automatically depending on the gap between cam profiles.