The Gunners had a busy summer window, with Arsenal smashing their transfer record on winger Nicolas Pepe.
Arsenal also signed David Luiz, William Saliba, Dani Ceballos, Kieran Tierney and Gabriel Martinelli.
Luiz was a deadline day singing from Chelsea after Saliba was loaned back to Saint-Etienne for the season.
The Gunners have been criticised in recent years for not going all out for a world-class centre-back.
Liverpool spent £75m on Virgil van Dijk before Manchester United splashed out a record £80m on Harry Maguire this month.
And Reds hero Carragher says Arsenal had a decent window despite breaking the bank for a centre-back.
“I read something that I found interesting because a lot of people were asking why they have spent £70m on Pepe when they need a centre-back,” Carragher said on The Last Word with Stan Collymore.
“The feeling at Arsenal was that they’ve got a great home record under Emery and their away record is awful.
“You’re thinking they actually need to score more goals away from home and they’re probably thinking, ‘You know what, there’s not a lot sometimes we can do defensively’ and to be fair I don’t know how many great defenders are out there because they’ve got a young kid, French lad (William Saliba) who they think is going to be the real deal and the Luiz thing has just happened.
“There is a dearth of great centre-backs out there so it’s not easy but I think they feel they don’t score enough goals away from home so that’s something that can add to them away from home.
“So I think they’ve done quite well. Yes, it’s top heavy but they will be exciting to watch.
“I never really had Emery down as that type of manager. He reminds me of Rafa [Benitez]… very studious and always very focused so you would expect his teams to be a bit more organised, not conceding goals left, right and centre.
“But it looks like that’s what we’re gonna get and they will go for the top four.”
Arsenal kicked off their Premier League campaign with a win at Newcastle on Sunday.
Pierre-Emerick Aubameyang netted in a 1-0 win at St James’ Park.