With the German now at the wheel and new management in place, the Italian team surged back to top form this season, finishing second overall behind Mercedes.
“Their return to victory was important for me and all of formula one,” F1 supremo Bernie Ecclestone told La Gazzetta dello Sport this week.
But Vettel acknowledges that the next step – actually beating Mercedes to the title – is a big challenge for 2016.
“We know that Mercedes will also improve for next season,” he said in Abu Dhabi.
“It is not enough just to catch up, we have to do even more.”
But that does not mean Ferrari will go radical for 2016, the German admitted. “The rules are not changing dramatically. So technically it will be more of an evolution of the current car,” Vettel said.
Ferrari, however, is now working hard on the 2016 project, he added.
“It’s not so easy to make big steps during the season, so it’s down to the winter to get the most out of it. This is our chance.
“We need to maintain our trend and make bigger steps than the others,” Vettel said.
He said 2015 was about regrouping after the turmoil of 2014, with the new structure headed by boss Maurizio Arrivabene and technical chief James Allison now working smoothly.
“It is much quieter than it was a year ago,” Vettel said. “We all know who is in charge and the mood in the team is good. The atmosphere is very positive.”