The current documentation notes a major constraint:

"Currently, one-directory depth is supported, but no more than that."

For large projects, keeping all unit tests flat or only one directory deep quickly becomes a maintenance nightmare.

The Improvement: Upgrade the test runner to recursively walk the file system.

Implementation: In Guile, you can easily use file-system-fold from (ice-9 ftw) or (srfi srfi-1) to recursively find all .scm files matching a pattern under VERITASSCANDIR, completely eliminating the depth limitation.