I’ve thought a bit about this, and I think it’s reasonable that entries demonstrating something wild like a completely new lisp implementation should probably get some bonus points for that; filing it under “creativity” is maybe not quite fair.
In a past jam, we had a 4th category for “Language use - how well was Lisp incorporated into the design” and I think that was added in order to address the same thing you mention: (this was before I was involved in running the jam)
Unfortunately it was not very well-received; people felt that it was unclear how to interpret and rate based on that criteria. I do think that if we used “Technical Merit” instead that it would be clearer than “Language use”. But it is rather difficult to gauge this by playing the game; would this mean that you need to read the source before you can rate the game?
I don’t know; I’m not against it altogether, but I’m interested in hearing what the rest of the community thinks.