Vince Cable and others have made it clear that they do not see themselves colluding with the Tories again, and may even end the coalition early. Probably quite wise to distance themselves from the evil selfishness that omits from the Tory Party.
Whilst on paper the Liberals look more radical than the Labour Party, they now have form for not doing what they promised – just ask the students. The biggest way forward for the Liberals would be to woo the unions, reinvent themselves as a party for the working classes, striding into grounds that Labour now fear to tread.