McKenna was speaking after their 1-1 draw with Fulham.
McKenna said, “I don’t think we can say disappointed because we brought in 12 players, if you count Omari (Hutchinson), who was with us last year, but it’s pretty much exactly there or thereabouts the numbers that we wanted to bring into the club.
“We end up with a squad of maybe 24 outfielders, about half of them have been with us on the journey, half of them are new. It’s a pretty good balance that we’re happy with.
“We’ve brought in some really good players to the football club, we’ve stuck to the plan, we’ve invested our bigger fees in young players with potential to grow and improve but who have good physical and technical qualities, and you can see some of them how they’re performing already out there.
“We’ve brought in some good, experienced professionals, who have worked really hard to get to the Premier League, who are starving hungry to make their impact and we’ve brought in some loans, who have high calibre and we think can help us.
“I don’t think we can come away from the window disappointed. Of course, you always want the squad to be as good as it can be. We’ve had two seasons in a row now of being a newly promoted team and you don’t get every target that you want, that’s the reality.
“We know in the pool that we’re swimming in in the Premier League, we’re not going to get every target or every player that we’re interested in, but that’s happened over the last two summers as well.
“I’m really happy that we’ve worked really hard, the club have invested to bring in players who will help us. We’ve been really stringent in terms of trying to stick to our plan, trying to bring in good characters, being really stringent on that as well, bringing people who will fit the ethos of what we have.
“And I think we’re left with a group that are desperate to do well for themselves in the Premier League and desperate to do well for the football club and all want to be here.
“I think that’s a pretty positive place to be and I’m looking forward to working with this group now for the next four months until the (January) window and the next 10 months or whatever it is of the season, and I’m sure they’re going to do some good things in the division.”