5x8 Teardrop with Kids Bunk--no galley

[KCStudly]

AC in the back has proven easier to seal water out for many people, so is probably a better choice. To get them to seal in the front most people resort to a tongue box like hatch style enclosure or a slide out with a sealed cargo style door.

[Socal Tom]

I'll probably just go with this design, but without the large side windows since I'll need to support the bunk area. This will allow me to place AC and storage in the rear--hopefully balancing the trailer a bit better.

One Idea I had was making the bunk so it could fold down--basically turning it into a cushioned back-rest for sitting. For example, if it's raining, we could fold the bunk down and play board games with our kids.

That looks like a good plan. You might consider adding a small RV access door in the back. If you put it under a seat of some sort, you would have a place for dirty stuff like a outside rug or tool box etc.
To,

[bknowles86]

If the majority of the loading is over the axle (bunks, etc) as shown in your last photo, would that mean you could potentially depart from the 40/60 rule of thumb and move the axle further towards the back of the trailer? New to the forum, so I could totally be missing the point.