Jesse, I'm sure Richard (Nileska) will not mind me adding my 2 cents regarding x-pen vs. crate.
I think most of us are in agreement that as long as the pup is confined
and not able to escape and possibly explore the house on its own, whatever method you choose is the right one.
Some people feel that one advantage to using a crate as opposed to a larger pen area, speeds up the house training as no puppy likes to go where it sleeps. I'm glad to hear that you have managed to take at least 10 days off at the start. That will really help you establish a routine. You may wish to save the x-pen for use a little further down the road when confinement is still necessary and housetraining is less of an issue.
I always add a word of caution regarding stuffing a kong with peanut butter, especially for very young pups and small breed dogs as it gives both of my dogs terrible diarrhea!
Even as adults, they can only have a wee bit of peanut butter or else. Some larger dogs do very well with it and it's good for them.
I think you will find that your puppy sleeps in bursts of 2 to 4 hours frequently throughout the day, as most dogs do all of their lives. If the crate or pen are comfy, safe and cozy, then that's all that really matters.