I do feel better marketing could have helped sell this game. I don't really think it got any...? Just some exposure would have been nice. I do feel making the gameplay more hack-and-slash would be more appealing overall, but the system they have now is fun as well.
If there is one thing I think they should change, it's the art style. Even I have to admit it's not very visually appeal, though not all characters look bad... If they change this with more marketing, I think it could sell better. If they make another Xenoblade-like game, maybe they can apply these changes and do a better job overall.
Dance my pretties!
The Official Art Thread - The Official Manga Thread - The Official Starbound Thread