Deciding between a lighter or darker accent wall depends on the effect you’re going for. Choosing an accent wall in a lighter color will make a room feel brighter and more spacious and complement rooms with less natural light. A darker accent wall will add drama and depth to a room and help make larger rooms feel more cozy and intimate.

Accent walls can feel out of place or distracting if not well designed. Accent walls that don’t fit in with a room’s style can feel jarring or overpowering. Some accent wall styles can also feel dated, but fortunately, it’s easier to update a single wall than an entire room.

When choosing materials for finishing basement walls, consider factors such as moisture resistance, durability, and fire resistance. Opt for materials specifically designed for basement environments, like moisture-resistant drywall or cement board. Insulation with vapor barriers can help regulate temperature and prevent condensation. Consider using mold-resistant paints or coatings. 

Research and consult with experts to select materials that are suitable for your specific basement conditions and intended use. Prioritize quality and compatibility to achieve long-lasting and aesthetically pleasing results.

If you can already see the texture of the existing wallpaper through the layer of paint, then the texture could also come through the new layer of wallpaper. If that’s the aesthetic you want, then proceed. But if you want a smoother surface, you should either strip off the existing paint and wallpaper or hang a layer of liner paper before proceeding.