Prominent figures in Glasgow City Council have described the current system as a "Thatcherite relic" and said its partnership arrangements with major bus firms was yielding limited successes.
It follows a poll by watchdog Passenger Focus which found Edinburgh City Council-owned Lothian Buses scored higher than or the same as the First Glasgow in all 34 categories of the survey.
Lothian passengers' satisfaction with value for money was eight percentage points higher than First's, at 79%, and satisfaction with punctuality was seven percentage points higher at 91%.
However, the biggest difference between the operators was the cleanliness of the inside of buses, with 88% of Lothian's passengers happy, 11 percentage points more than First's.
The poor comparative polling by the First Group-owned firm compared with its Edinburgh counterpart has led to the former head of the west of Scotland's transport quango calling on the Scottish Government for a new system of regulation.
Alistair Watson, former chairman of Strathclyde Partner-ship for Transport and now head of roads at the city council, also accused the SNP of putting its relationship with Stagecoach owner Brian Souter ahead of a new system.
He said: "De-regulation of the bus industry has failed. The current system is a Thatcherite relic and the party in power at Holyrood understood that fact right up until the day they cashed Brian Souter's first cheque."
Local authorities are not currently responsible for regulation of the bus market.
There have been a number of unsuccessful attempts to bring in legislation at Holyrood that would re-introduce regulation.
Councillor Watson said: "In the absence of meaningful regulation, we have worked with partners to create partnerships. But they are limited in what they can achieve. The council strongly believes the industry should be regulated and we have supported the numerous attempts to introduce legislation that have been made in recent years, all of which have been voted down by the Scottish Government."
Glasgow Green Party MSP Patrick Harvie also repeated his call for greater control of bus services to force improvements, adding that the push to encourage more people to make the shift to public transport required "offering an outstanding level of service".
A Transport Scotland spokes-man said: "We are delighted to see both Lothian Buses and First Glasgow scoring so highly in the recent Bus Passenger Survey with overall passenger satisfaction scores exceeding 90%.
"We are not convinced that wholesale re-regulation is necessary or affordable, but we will look closely at any serious and specific proposals."