A puffer is not like some of the big cichlids.
For a lot of the big cichlids they just want to defend a log all day so that is all they need.
The puffer is more of a thinking fish. It wants to interact with the environment and look for new things. Think more like building a tank for a kitten. You need to make different areas for it to explore so it has fun. I would stack rocks to make various holes big enough to swim through and use driftwood to make something elaborate for it to hunt in.
Plus the tank will look better for your eyes as well.