But achieving consensus proved difficult among nations at vastly differing stages of development with a collective population of two billion people spanning the globe.
"We as leaders have taken some major reform decisions this week," said Australian Prime Minister Julia Gillard, the host.
"Some of the discussions have not been easy. Getting consensus in an organisation as diverse as the Commonwealth is never easy. But we have achieved and agreed a lot.
"I believe we have made a major contribution to ensuring the Commonwealth is well positioned for the future," she added.
The EPG said an independent commissioner overseeing human rights, democracy and the rule of law was vital to reform the organisation, but agreement could not be reached.
Instead, leaders said they would further evaluate the proposal and report back to foreign ministers next year.
Of the EPG's 106 recommendations, 11 were dismissed as "inappropriate", although the communique failed to go into detail.
Many others were adopted though, including the need to do more to combat climate change, a commitment to avoid trade protectionism and the need to work to improve gender equality.
Leaders also highlighted the importance of a strong response from the international community to restore confidence in global markets amid the eurozone debt crisis.They confirmed that the next summit in 2013 would be in Sri Lanka, despite concerns over alleged war crimes by the Colombo government during a final push to defeat Tamil Tiger separatists in 2009.