This is mainly a question for @zarf…
I am working to package glktermw for Debian, and our ftpmaster team noticed that the glktermw license permits modification of the code but not the documentation, and as such doesn’t meet the Debian Free Software Guidelines.
This might be resolved by changing “incorporate this code” to “incorporate this code and/or documentation”. Or, more preferably, you could adopt a similar license already in wide use; a list at https://wiki.debian.org/DFSGLicenses may be helpful. The MIT license, in particular, looks quite similar to yours.
Would you be open to making this change?