They lost six games by two goals or less this year and ultimately fell one win shy of the top eight.
Van Berlo said the side's results over the past two seasons was proof change was needed, particularly in regard to the team's defensive ability.
"We have to be aggressive in that manner because the reality is, we've just narrowly missed finals the last couple of years and for whatever reason … we need to get the best people in here at the football club," van Berlo said.
"The players are on notice that if there is someone that can better your position or better the football club, we'll look to try and get them in.
"Our defence needs to improve and I think that's where we'll focus most of our effort … when I say defence I mean team defence."
One player who the skipper hoped would stick around long-term was midfielder Patrick Dangerfield.
Dangerfield is out of contract next season when he's set to become a free agent.
As one of the most explosive and marketable players in the League, the 24-year-old will attract a huge amount of interest from around the country.
Teammate Rory Sloane also falls out of contract next season but recently stated he was keen to remain in Adelaide past 2015.
Sloane said keeping Dangerfield and Taylor Walker at West Lakes could see the side achieve big things in the near future.
Sloane and Dangerfield captained the Crows in 2014 in van Berlo's injury-enforced absence.
Van Berlo said he would like to resume the captaincy next season but that regardless of who led the club, it needed Dangerfield to re-commit.
"I love leading the club and it's been a huge honour for me, I guess we'll have those discussions in due course," he said.
“’Danger’ is essential for us moving forward in terms of where we want to get to as a footy club and he's a real loyal character as well.
"I'd love to see him stay at the footy club.
"He's pivotal moving forward in a leadership sense and definitely on-field in terms of what he gives us."
A ruptured Achilles suffered during a freak training accident in January ruled van Berlo out for the season and forced him to watch on as the Crows struggled to string consistent performances together.
The 28-year-old endured a frustrating six months but said he had tried to look at the positives.
"I guess I'll have an 18-month pre-season now to get myself up and going for 2015," he said.
"I've tried to be optimistic about what 2014's given me and it's the freshest I've ever felt going into an off-season."