Allow Rule Set variables to match anything

I want to create a Rule Set where one or more variables are optional.

For example, a rule might match new conversations when they arrive in specified mailboxes, from specified senders, with specified words in the subject, and notify specified teammates. However, sometimes I might want all messages from certain senders to be matched, regardless of the subject. There's no apparent way to accomplish this with a single Rule Set.

Allowing the use of wildcards (asterisk, etc) in Rule Set variables would do the trick. Or allowing variables to remain empty and be treated as a match-all.