Make a 'fast' subset of the testsuite
The testsuite takes a long time to run (usually over an hour, but depends on what "ways" are enabled).
It would be extremely useful to have a subset of the testsuite that runs far more quickly, and yet tests a large proportion of the "useful" tests. For example: omit all ways except normal, omit "programs", and pick a representative few from each of the test categories leaving out long-running tests. We pick a target of running the fast suite in, say, 2 minutes.