since the latest release, Slime seems to have moved quite fast and requires quite advanced MOP features (namely, functions for querying method keywords, COMPUTE-APPLICABLE-METHODS-USING-CLASSES, etc).
FWIW, I think most (if not all) of the MOP stuff is needed by the inspector. If you think this mop-stuff is too complicated ATM, you probably won't break anything essential IIRC.
- ts