"For all its faults", it said, "another Lib-Con Coalition would both prolong recovery and give our kingdom a better chance of continued existence".
But it hoped it would be "much less conservative, and much more liberal".
The Guardian has backed Labour and the Sun the Conservatives - with its sister paper the Scottish Sun backing the SNP.
Other papers which have declared support for a specific party so far include the Mirror, which is backing Labour, and the Financial Times, which called for another Conservative-led administration.
The Independent said it was not telling its readers how to vote but it said it believed democracy was precious and must be revitalised.
It said the Greens had been a "disappointment", while UKIP were against "globalisation and modernity, both of which we welcome".
"The SNP is an agent of change, with impressive leaders in both Alex Salmond and Nicola Sturgeon. But they are a wrecking ball poised to hit Westminster and, unlike us, want to abolish Britain," it said.
It said Ed Miliband had had an impressive campaign, but criticised him on various policies - and warned of any partnership between Labour and the SNP.
"For all his talk of no deals with the SNP, Miliband is bound to rely on that party to get his legislative programme through," it said.
"This would be a disaster for the country, unleashing justified fury in England at the decisive influence of MPs who - unlike this title - do not wish the union to exist."
On the Conservatives, it criticised areas such as "excessive austerity" but said the economy "is now growing reasonably well".
"Many of the good things the coalition has done are owed to the Liberal Democrats," it said.
It particularly picked out "raising the income tax threshold, the pupil premium, early years learning and apprenticeships" as areas where the Lib Dems had been a force for progress.
It concluded: "For all its faults, another Lib-Con coalition would both prolong recovery and give our kingdom a better chance of continued existence.
"This title casts no vote.
"But we prize strong, effective government, consider nationalism guilty until proven innocent, and say that if the present coalition is to get another chance, we hope it is much less conservative, and much more liberal. "
The Sun - Conservatives
Scottish Sun - SNP
Mirror - Labour
Express - owner Richard Desmond has given Â£1m to UKIP
Financial Times - has called for tactical voting to produce another coalition between the Conservatives and Lib Dems
The Guardian - Labour
Daily Mail - backed the Conservatives in 2010 - as did the Mail on Sunday
Telegraph - both daily and Sunday editions backed the Conservatives in 2010
Observer - backed the Liberal Democrats in 2010
The Times - backed the Conservatives in 2010
Independent on Sunday - said it is not advising readers how to vote in 2015
The best of BBC News' Election 2015 specials
The Independent newspaper has given its backing to another coalition of the Conservative and Liberal Democrat parties after the general election.