Luis Enrique will stand down at the end of the season with his current assistant Unzue, Athletic Bilbao boss Ernesto Valverde and Real Sociedad coach Eusebio Sacristan leading the race to take over at Camp Nou.
Roberto, the Barca hero in their dramatic 6-1 Champions League win over Paris Saint-Germain earlier this month, came through the ranks at La Masia and believes Unzue's ascent to the top job would be good for continuity purposes.
The Spain midfielder told TV3: "It would be a great way of maintaining Barcelona's philosophy. We have a great relationship with him.
"Even though he is technically in charge of strategy, he always gives us very good tips overall.
"He would be a great coach for Barcelona."
When you get to suffer an eternal 'rondo' at Barça pic.twitter.com/yHV88B8svc— FC Barcelona (@FCBarcelona) March 24, 2017
Barca will face Juventus in the Champions League last eight after their 6-5 aggregate defeat of PSG and Roberto accepts it is another tough assignment.
"As your typical Italian side, they are a stout defensive team," he said.
"Moreover, their attacking players are incredibly skilled, so we know that advancing to the semi-final will be far from easy.
"Winning another Champions League would be very exciting, there is no doubt about it.
"I wouldn't say it is a priority for us, but it would mean a lot to win it after the comeback."