I would totally recommend Hotel Axel in Barcelona. Actually it's a theme hotel, maybe not very suited for business travelers, but it's super comfortable for all sorts of visitors. The location and the building are wonderful, the rooms seem to be well maintained, clean and tidy, comfy beds. Reception staff is absolutely great. I got an upgrade and the room was very nice. I didn't manage to test the spa and the roof bar so I can't say anything about those.
On the negative side - the bathroom amenities are a bit poor, the minibar in the room is too pricy, the streets outside are very noisy even if the neighborhood is calm and the housekeeping staff is shouting around the corridors all day so it's difficult to rest or work during daytime. Nevertheless, this is a unique, relaxing and highly recommendable hotel to stay at when visiting this chaotic city, and I will definitely be back there again in the future.