QUESTION: How should we deal with a brutish mars, like Mars in a familial house (2, 4, 7, for example, even 5) or Mars in a gentler sign (like Venus signs)?

Ferociously defend your family, and protect the rights of everyone who is under your care or your responsibility in any way. Be willing to die protecting them. Be very imposing and terrifying to any potential threat towards them.

At the same time be soft as a flower towards the people you are protecting.

This balance will engage your nature (dharma) the way it has to be engaged, but will also prevent it from being out of control and counterproductive.