Hey!!! I reached here from a reply you left on my comment, and I have to say, your book is amazing!
Just a tip from a fellow writer: Every time you write a dialogue from a different person, start on a new line.
Like this:
Keith, tired from an exhausting day of rescuing space aliens, slid down into the seat next to Lance. Which, unfortunately was the last one left.
"Keith, change seats."
"Uh, this is the only one left."
"Oh, come on!"