Let's be honest, one's imagination has very little influence here. For now character costumization is rather lacking and posting the same 5 recolored faces with different hairstyles isn't particularly inspiring or skill consuming. I miss actual costumization we've kind of gotten used to with say DAO or DAI.
I'm not saying customization isn't lacking, though the severity of it is up for debate.
It's entirely possible to create a four man party that looks unique. What we're seeing is limited because people favour Humans & Drow/Elves, there's only so much Larian can do there.