Groups vs tags for broad categories

I was wondering it is best to use tags or groups for large categories like straight, lesbian, couple, threesome etc.

As a corollary, it would be kind of tedious to create a group for each possible combination of performers e.g. 1 female 1male, 2 females 1 male, 1female 2 males, 2 females 2 males etc.Is it possible to filter scenes by the number and genders of the performers?

Only by number using Performer Count filter.