Swamp hideout - exploration & layout

Here are some of the steps from one of my latest projects, in exploring a fantasy medieval style hideout in a swamp.
The brief was that it should be incorporated into the landscape, yet still reach out via a tower for lookout.
Also it should be functional and align correctly.

In the thumbnails I explored various culture styles and choose two of them which I painted in product view.
Beforehand I planned the space accordingly to fit the brief. The functional layout with stairs, doors and windows came first.

The next step is the blocking in 3D to get some entertainment paintings of the outside, whilst planning the interiors for the character housing there.