I think (10.) will be closest to the real answer.

General Relativity only needs a small tweak, which I argue is to combine GR with the concept of global discrete conformal invariance, i.e., same physics on radically different scales. On the other hand, this would mean that many cherished assumptions and ideas from quantum physics will have to be replaced or reinterpreted.

If the dark matter has virtually nothing to do with subatomic particles, but is actually what Discrete Scale Relativity predicts: stellar-mass primordial black holes, then we may have the humility and scientific integrity to admit that the physics of the microcosm must be revised in major ways.

Below are some hints from nature that this must be the case:

NATURE’S STARTLING CLUE — CONFORMAL SYMMETRY