Davis Cup organisers say they are already considering changes to the new competition's format.
The first edition of the competition's new format is not yet over but the CEO of the group behind the revamped team competition said things need to improve.
Kosmos Tennis CEO Javier Alonso said on Friday that although the tournament has been an overall success, organisers need to work on ways to increase attendance and improve the scheduling of matches.
"Again, it's the first edition," Alonso said.
"We make a plan, and now that we have the reality, we can go back home on Monday and start thinking on what has not worked well and how we can improve those things that have not worked well."
He said the most pressing concerns are related to the schedule of matches and low attendance, especially in the morning sessions.
Only matches involving host Spain have had full crowds, although the fan atmosphere at most matches has been good thanks to the travelling groups of supporters from some of the participating nations.
"We knew that mornings were difficult. Not only here, everywhere. But it's a learning again," Alonso said.
"Now, with the experience, we will do it different next year."