The report by the Independent Police Complaints Commission said riot officers should hand over batons used during confrontations so they could be stored as evidence.
But the Countryside Alliance said the recommendation showed the commission had not dealt with the "strategic failures" by the Met Police during the protest two years ago.
Around 1,300 police officers were moved in to Parliament Square on September 15, 2004, when at least 20,000 people descended on Westminster to protest against the proposed ban on hunting with dogs.
It was more than double the number expected by the Met and when a group of protesters tried to break through a police cordon there were violent exchanges between riot officers and demonstrators.
Missiles were thrown at police and barriers pulled down by protesters while officers retaliated with batons.
A number of demonstrators were left with serious head injuries.
The commission said it investigated complaints from 54 people who claimed to be injured by police officers and also from 119 people who were not hurt.
The Met claimed more than 60 of its officers were injured.
Criminal charges were brought against seven Met officers following an investigation but all were either found not guilty or had their cases dropped.
Two officers faced an internal tribunal but in both cases no action was taken after charges against them were found "not proven".
Today's police complaints commission report, published following the conclusion of all the criminal cases, said there were lessons to be learned by all the parties involved.
It recommended the Met should "as a matter of urgency" review the options available to officers attacked while in a police line.
The Met should also consider crowd "dynamics" when planning for a protest to ensure escape routes are provided for demonstrators.
But apart from other specific recommendations on clothing and form-filling, the other main conclusion drawn by the commission concerns batons.
It said that where batons had caused injury, "procedures should be put in place which identify the officers who have used their batons.
"The batons should be retained by senior officers, and they should be correctly identified and exhibited, and should be stored in containers individually, which allows for further forensic examination if necessary."
A Countryside Alliance spokesman said: "This is not about whether or not officers bagged each truncheon as evidence after hitting a protester, this is why senior commanders in the Met allowed the situation to get out of hand.
"We are not angry about the fact that no officers have been successfully prosecuted, what we are angry about is the fact that they were put in the position where they felt they had to use force."
He added: "Everyone agrees that something went very badly wrong with the policing of that demonstration, but we have a report that doesn't even seem to touch on the strategic failures of that day."
Since the protest new laws have been passed forcing organisations planning protests in Parliament Square to obtain a licence from the police.