Yoshi-P has stated a few times before that they were working to expand upon the current houses that are already bought rather than add in more housing. Considering that they have never added anymore spaces inside the houses but flooded us with furniture, it's definitely an update I look forward to.

They did mention something about Ishgard housing but they also noted that it wouldn't be out before they found a way for people who had a house to basically be able to move to Ishgard without selling/abandoning their houses (and having to buy them again).