To clarify and deepen my understanding of the Mice, I pondered the following comparisons with similar and/or opposing cards. Maybe my comparisons will inspire you to make your own!
Secrets
Mice: Harmful and/or malicious secrecy. Something is being done behind someone's back. Sneakiness.
Clouds: Something is being hidden from view, fogged over - not necessarily with bad intentions, possibly just for self-protections or out of shame.
Book: A "secret" in the sense of esoteric knowledge - not everyone has access to some type of knowledge or information.
Key: The opposite of secretiveness: openness, straightforwardness. Or: to find access to a secret.
Birds:
To blab a secret.
Loss
Mice: Loss in the sense that something has been taken away, stolen, or that something which was once plenty is now getting less, dwindling away.
Coffin: The experience of a very painful and permanent loss. Something or someone is gone for good. The grief we feel over an ending or loss. End; death.
Ship: Loss in the sense of "someone has left" or "something is absent right now" (but they might return).
Whip: Sudden, painful loss, especially in the sense that someone or something is cut (off). E.g. loss of job, loss of limb, to lose someone through an accident.
Little/Much
Mice: Scarcity; loss. Few, less of. Not enough.
Fish: Abundance, accumulation. Lots, enough of. Too many/much.
