First off,,, what a beauty! Secondly, that's the reason we have boas. We don't want them trembling and scared in a hide 24/7 like mine that hasn't eaten since X-mas Eve.
You have perfect behavior with yours. Those vines you have are providing a "top cover" which is pretty natural. She feels secure and probably feels like the area is great for ambushing prey.
The beauty is she is visible to you!! The best thing about snakes when we are not feeding them, is to see them. Moving or resting does not matter. My boa likes his perches and stays on them.
Our Royal is the basically hidden all the time and I could have an empty tank and not know the difference.
Its the reason I went boa. I have 2 great snakes in my son's Royal, she is easy, mellow and a joy to handle but boring and and the boa which is all of the above, but also social and much more active.
You are doing great! Enjoy that characteristic!