Ashley Williams joined Everton for $21 million before the season began, while Andre Ayew moved to West Ham and Bafetimbi Gomis signed for Marseille but Fer, who made his loan move from QPR permanent, is not expecting a relegation battle.
Swansea beat Burnley 1-0 in their opening fixture, but have since lost 2-0 to Hull City and 2-1 to Leicester City, leaving some to question whether Francesco Guidolin can improve on last season's 12th-place finish in the Premier League.
As well as Fer, Guidolin signed Borja Baston for a club-record $27m to strengthen his side, and Fer told the Guardian: "Some good names – Ashley [Williams], André [Ayew] and Bafé [Gomis] – went to other teams in the summer, that's a big loss. But we had some new players come in and I still think we've got a strong team.
"To be fair, when I went from Norwich City to QPR, because QPR came from the Championship, I had that feeling a little bit: 'Is this the right option?' I joined and got relegated again, and that was hard for me, playing in the Championship for six months.
"Swansea were struggling last season. But I could see we had enough quality."
Fer's career began at Feyenoord in his native Netherlands, and he played for FC Twente before moving to England with Norwich.
He then made 50 appearances for QPR before joining Swansea, and he is enjoying life outside the capital.
"With QPR, I was playing for one of the smallest clubs in London, and you can do whatever you want in the city and nobody knows you. But here it’s different, they treat you like a king," he said.
"You go out to eat, some people are waiting for a table, but we get one straight away. I don’t like that, so I say: 'Leave it, give the table to them.'
"I also get free popcorn when I go to the cinema – I'm happy to take that."