The Villans, who went up via the Championship play-off final last season, have been one of the busiest clubs in the top flight following a host of new arrivals.
Wesley, Marvelous Nakamba, Tom Heaton, Matt Targett, Douglas Luiz, Jota, Ezri Konsa, Bjorn Engels and Trezeguet have all joined, while Kortney Hause, Anwar El Ghazi and Tyrone Mings have made their loans permanent.
With £130m thought to have been spent to add reinforcements over the summer, Smith feel his squad are in a good place going into the start of the Premier League campaign.
"What other teams do is their business," Smith said. "We know what we have to do at Aston Villa and I am very happy with what we have done.
"We believe we have done a really good job this season. The fact is we lost 15 players we had to replace. What was important was we kept the core of the squad and the heart of the dressing room is still here.
"We want people coming into the club to realise there is a culture of winning, improvement and development. We are happy with the signings we have brought in and the recruitment policy we adopted."
As well as the new signings, Villa were able to tie midfielder John McGinn down to a new contract with the West Midlands outfit.
The Scotland international was a key figure in helping the club make a return to the top flight and his efforts in the Championship saw him linked with moves to some of the top clubs in the Premier League.
Keeping hold of the former Hibernian man, who was strongly linked with a move to Celtic, comes as another massive boost for Smith ahead of the start of the Premier League season.
Villa start their campaign on Saturday when they make the trip to north London to face Tottenham Hotspur.