I had just snuggled down in my bed and was thinking about various things when it came to me why you don't see bunks going front to back in teardrops.....The Doors!

Nobody mentioned the doors yet! If you build a bunk or bunks that way, unless you put the door in the front or back, you're going to be cutting into the door opening's headroom.
If you figure that you need at least 18 inches from the bunk to the ceiling and the door and roof framework usually takes up at least 3 inches and you're going to want a lip on the bottom of the door of at least - best guess, 2 inches, in a 4 foot tall teardrop, that door is going to lose 15 inches of height, which is a lot because that effectively gives you a door that can't be any taller, bottom lip to top, than 31 inches ..not big enough. Now, if you add the extra 6 inches in height to the sides(we talked about that earlier), that would give back 6 of those 15 inches, making your door opening around 37 inches and that would most likely work.
Of course, the hammocks, being soft sided, would not be much of a problem; but, if you ever want to add the bunks, you'd need to decide and build accordingly now.
...Just a thought.
