You know what's hard? Names.
Naming a character has a massive impact on how readers first view a character. It's strange, but you automatically begin to make assumptions simply based on what the writer decides to call someone. Pictures pop to mind if you read Abner Snodgrass or Mildred Grimes as opposed to Ace Hunter or Sydney Miles.
So, you want the name to sound right, be evocative, and have some meaning behind it. After all, you will be using it an awful lot.
I've been struggling over names for my new work for weeks now. I think I have one so far. Ugh.