You only have 3 different levels:
- 0 (quiet): you just get the total numbers of tests executed and the global result
- 1 (default): you get the same plus a dot for every successful test or a F for every failure
- 2 (verbose): you get the help string of every test and the result
You can use command line args rather than the verbosity argument: --quiet and --verbose which would do something similar to passing 0 or 2 to the runner.