I know I can .
Right Join can also be written as left join. So there is no need ever to use Right join.
when Inner, when Left, when Full outer ? It depends on the business requirement.
"Give me all entity1 with their entity2's" is a typical inner join.
"Give me all entity1 and if they have entity2's give those too" is a typical left join.
"list me all entity1 and entity2 with the differences" is a typical full outer join