[mtlmtlmtlmtl]

They are both fields, but gravity is different in that spacetime itself is the field.

As for the weak force, I think that's not necessarily a known property of DM, but rather a property of hypothetical candidates for being the dark matter known as WIMPs(weakly interacting massive particles).

[wiml]

AIUI, dark matter has to have some non-gravitational interactions in order to cool enough to produce the observed "clumpiness".