Decorations - to suggest they are needed almost seems silly in Minecraft, at first. You have weapons, armor, explosives, even primitive electronics...who needs decorations? As it turns out, anyone who wants to flesh out their build with those final touches, the ones that turn a house, castle, ship, or whatever else from merely a building, to a home, a fortress, a unique place to be.
That said, Decocraft is a mod by Razzleberryfox (with framework by Noppes, and contributed to by ProfMobius), which does exactly what the name suggests: adds decor! More specifically, props - or interactive, sometimes movable objects meant to enhance a build - and there are no small amount of props included here, over 300 models total so far! Decocraft continues growing constantly, and new props are added all the time.
Currently, Decocraft is supported for versions 1.7.10 and 1.6.4. If you have ever wanted to add proper furniture, lights, games, or other interactable elements to your build, consider giving Decocraft a try!