How about enforcing coverage? I know that coverage tests don���t say anything about the quality of the test cases but it���s (almost) always better to have some tests than none. I wouldn���t set the bar too high either for coverage, maybe 60 or 70%. 100% is unrealistic, but 60 to 70 should be achievable with a couple of well written tests.
Of course we would need a way to run coverage tests on the test suite. Do we have a tool for coverage tests?