The South Korea international found himself something of an outcast under former Swansea boss Michael Laudrup, but has been offered a second chance to shine by the Dane's successor Garry Monk.
Ki is confident he has more to offer the Welsh club this time around, and attributes his improvement to his time on Wearside last term.
Asked whether he felt he was a better player than the one who initially arrived at the Liberty Stadium from Celtic in 2012, Ki told Swansea's official website: "Yes, I think so.
"It feels like a new start for myself and everything has gone well so far.
"It was tough at Sunderland at first because we had a new manager [Gus Poyet] and the team wasn't right. But as time went by we developed and we survived.
"I have grown up a lot and I have a lot more confidence and experience.
"This is my third season in the Premier League and I want to grow as a player and improve to help the team."
The 25-year-old is also hopeful Swansea can mount a challenge for a top-half finish this season, having ended the 2013-14 campaign in 12th.
While the likes of Ben Davies, Michel Vorm, Chico Flores and Michu have moved on to pastures new, the latter on a season-long loan to Napoli, Swansea have brought in a number of players, including Bafetimbi Gomis, Lukasz Fabianski, Gylfi Sigurdsson and Jefferson Montero.
"It is a tough league, and every game is difficult," Ki added. "But our squad is very strong and every player has quality, especially the new signings.
"We want to be better than last season and finish in the top half."
Swansea kick off the new season at Manchester United on Saturday.
