The Marxist view of the family is all about it being a tool of capitalist oppression, and never mentions the benefits.
Marxist sociology is entirely focused on benefits to the economy, and benefits to the working man's boss. It ignores other benefits to individuals and society.
Traditional Marxist sociology assumes that the worker is male, and that women are housewives.
There is no Marxist explanation for why the family flourishes as an institution in non-capitalist or communist societies and there is little Marxist research on alternatives to the family.