England boss Shaun Wane says there are still "10 spots up for grabs" with the World Cup just four months away.
Wane's side beat the Combined Nations All Stars 18-4 in Warrington, 12 months after being on the losing side.
Despite name-checking captain Sam Tomkins as the "nailed on" starter at full-back, Wane warned the Catalans Dragons player he too "would be out" if his form dipped later in the season.
"The review of this game won't be great," said head coach Wane.
"I need certain things fixing that are unacceptable. The players know that is coming and they are the ones that are picking that up. It is a great learning experience for everybody.
"We will analyse the game and it will be fed back individually and collectively to the players. The World Cup is not far off and the players need to take the feedback onboard."
England begin their World Cup campaign on 15 October against Samoa in Newcastle but have just one more warm-up fixture remaining between now and then, coming up against Fiji in Rochdale.
Huddersfield's Jake Wardle scored on his England debut, while Warrington's out-of-form scrum-half George Williams and Wigan forward John Bateman were also on the scoresheet.
England gained revenge after being beaten by the All Stars 12 months ago in Wane's first game in charge of the side.
After Wane pronounced himself "really impressed" by Tommy Makinson, the St Helens winger and club team-mate Alex Walmsley look to be the only two other players who are shoo-in starters for the tournament.
"I am not sure John is one of [the starters]," said Wane. "I would say three or four are nailed on but if their performances dip this year, the door is open for others and I genuinely mean that.
"I am not bothered what other people think, I will listen to my well-educated coaches and if someone is playing well it is an open door and anyone can force their way into the England team. That is a real positive for us.
"I honestly mean it when I say there are more than 10 spots still up for grabs. I like Sam and he did some good things, some ordinary, but he will be nailed on for the full-back. If his form dipped he would be out. The players would not expect anything else.
"I think it is exciting. Jake Wardle will read these comments and think he needs to play really well for Huddersfield. Everybody else who is not playing, they know. Dan Sarginson [of Salford] is injured and knows I will pick him if he is flying over the next few months."
Rugby league legend Ellery Hanley took charge of the All Stars and said England "deserved to win" but have work to do in the lead-up to the World Cup.
"There are some areas England need to work on and are vulnerable in," he said. "We had three or four chances where we could have posted tries but you have to be aware of that and not paper over the cracks. Shaun has the players onside on what they have to do to win a World Cup.
"I think it will be a wonderful World Cup with all the sides in but the obvious big three are Australia, New Zealand and England. They will compete for the trophy."