First of all, put out the external lighting. You do not really have it and from this scene as a whole is faded and there is no contrast, there are no natural shadows. And maybe it will not make sense to use AO, which is also incorrectly configured. With all the materials of the tree, I also think so the problem both in terms of settings, and in terms of mapping. A carpet can not grow out of the floor. Turn on the chandeliers, rework the lighting of the ceiling, the illumination of the bookshelves.
ps In general, your main problem is light / lighting. Work out and put out the lighting on the Sermat, and after that, refine the materials.
