I find it useful if you want to use the houses as buildings. I have a second profile to use the house as an inn with themed bedrooms. Was hoping it would unlock extra design space but it doesn't. That and all the extra space to get resources and paintings from Red. I plan to make another profile and make a house for my sister in her style (she passed recently) as a tribute to her. So, perks are more creativity, resources and just use of extra space if you have empty space on your island you don't know what to do with. 
