The rococo and classic sets are probably the ones I like the most so far but others I enjoy are the minimalist, sweets, gorgeous and princess sets. Oh! I forgot to mention the regal and patchwork sets as well! Those are also great!
my favorite furniture set probably has to be minimalist. it's very simple and it can go with pretty much whatever you put in the room. it also has a modern vibe to it. less is more.
Even better is the pink and white customization for said lovely set. And even EVEN better is being able to use a Lovely Dress as the material for things like the lampshade. It's just cute pink hearty overdose.
My favorite furniture sets (as is, with the original color scheme) are Sleek and Gorgeous. They're just really classy, and I like how the Sleek set can match with quite a few things.
Other sets I like are Robo and Astro, but only when they're customized to Red/Black and Red.