Revising your process flow to put temporary data in WORK and materials that require persistent storage on an explicitly named LIBNAME is the only way to really tame the beast. E.g. Plan ahead.
Systematic delete of everything in SASUSER is not a best practice because it gets used for so many things, so there may be unintended consequences. However, it is a business decision that may also be appropriate in some cases.
Even though it is the default for much of EGuide, I avoid the use of SASUSER as much as possible. SASUSER is on the workstation and, in my organization, it is not backed up.