Hi Matt,
This is something that we'd need to evaluate a bit further putting on the roadmap, but in theory the lead scoring engine and algorithm should be able to support custom profile and engagement levels. The primary reason for the 4x4 grid is ultimately current best practices - which as you know are always evolving based on what marketers are trying to accomplish, so thank you for your feedback
Unfortunately can't commit to any timeframes for delivery, but will definitely add this as a feature request for us to evaluate further.
Taha