So, you’re assigned a 20-page paper when really you’re only used to 5-page papers. That’s pretty daunting. It’s a lot of space to fill. Therefore you’ll have to fill it with a lot of stuff. Four times as much stuff. Four times as large a topic. Four times as significant a claim!
Except that that’s not right at all. That’s the wrong multiplier. Go down that road and you’ll start trying to develop new theories of renaissance post-modernism, or a comprehensive description of the minority female healer in the modern consciousness.
A better multiplier is nuance or detail. Four times as much nuance is a wonderful thing.