One of Barca's greatest modern players, Iniesta left the club at the end of last season after spending more than 22 years with the youth teams and senior side at Camp Nou.
Iniesta won a remarkable 30 major trophies for Barca, including four Champions Leagues, the last of which came in the treble triumph of 2014-15.
The Catalans have since endured frustration in Europe, though, failing to progress beyond the quarter-final in each of the last three seasons while watching Real Madrid lift the trophy three years running.
While he is proud of his achievements and does not feel resentment towards Madrid's success, Iniesta concedes he would have liked to add to his collection of Champions League triumphs.
He told Club del Deportista: "I don't feel angry. Of course, I'd have liked to win more Champions Leagues. Who wouldn't? But I think the people have to feel proud of what was achieved, because it made them happy.
"Beyond that, you can't do anything. Madrid won Champions Leagues, they'll be happy about that, and they won't be happy for having not won the league titles that other teams won.
"It's true Barca had the squad in the last few years to have been able to take another step forward in the Champions League."
Iniesta, now at Vissel Kobe in Japan's J1 League, hopes to return to Barca in the future in a non-playing capacity.
"I've always felt important. I decided to leave because I saw the moment had come when I felt I'd given everything to my club, that I'd left my soul there," said the 34-year-old.
"I made the decision for a change of air, of country, of dreams and challenges. That's what my heart and my body determined.
"If it were up to me, I'd go back. I don't know what will happen in the future. Making long-term calculations right now is difficult."