Thanks for the feedback! I generally try to use dark oak, spruce and oak wood because they tend to have colors that fit the style of the build. Since darker log seems 'tougher" in a sense, I tend to use spruce wood at the bottom along with stone brick, and oak wood higher up in the build, but I would try to only use dark oak at places that supports a lot of weight, such as the bottom of the guard tower or places where the color feels too bland.

I have definitely experimented with the arches with this build, the roof originally came out too be too large, so I decided to create a new design to fit it, and while it was hard trying to build it, it ended up fitting the theme of the build better, so I am really happy with how it turned out.