Andrew Wilson also proposed former Liberal Democrat Scottish Secretary Michael Moore could play a part in the negotiations that would have to take place if Scots voted to leave the UK.
The former MSP, who left Holyrood 10 years ago, said senior representatives from the pro-unionist parties would have a "clear stake" in such talks.
He told the SNP annual conference in Perth: "When we win all of the current opponents of independence will cease to be opponents of independence and should be given a clear stake in shaping the outcome to embed its legitimacy.
"Maybe our two former first ministers and one former Labour, Tory and Lib Dem Secretary of State for Scotland, Michael Moore for example, could be included in the team negotiating the terms of independence and Scotland's relationship with the rest of the UK."
His comments come after Deputy First Minister Nicola Sturgeon said unionist politicians would be invited to take part in the negotiations for Scotland to leave the UK if people voted for independence next September.
In a speech last year Ms Sturgeon said while it would be the SNP Scottish Government leading the negotiations, she wanted others to contribute in a ''team Scotland'' approach.
Today Mr Wilson, a former SNP finance spokesman, stressed that the "referendum is not D-Day but day one, and in an era of transformation and reform around the world, this party has to be confident in leading reform in this country whatever the result next September".
The former MSP, who was giving the Donaldson lecture at the conference, said the world was going through an "epic era of reform and transformation that could continue for a decade and more".
He added that "every major institution in life" was going through change, with the monarchy, churches, parliament, banks, the media and others all being "shaken to their foundations by the relentless scrutiny of the public gaze exposing every frailty in real time".
He told the conference: "The way things are and have been is changing now and forever and the sooner we face up to that reality the better."
The independence referendum, which is being held on September 18 next year, "sits very neatly into this context of this global reform", Mr Wilson said.
In the run-up to the key vote, he said Nationalists must be careful when making "negative" remarks about the United Kingdom.
He said that in the debate over Scotland's future "the more emotional, negative and puerile arguments come from the No Campaign at all levels".
While he said those campaigning for independence should not "forget to point out the negative realities of the status quo" he also said they should be "be careful how we do that".