Perhaps the government could pay for unemployment insurance or benefits when there is reduced work for gig employees. The government can fill in the gaps to make sure business have access to a stable pool of gig workers with the ability to retool for different gigs.
There's a stable pool of gig workers right now, which success of Uber and alike demonstrates very vividly. So the availability of the workers is not a problem which needs to be solved.
Sorry for being unclear by my use of stable pool. I meant to say that the pool was stable in the sense that it was healthy and sustainable for people despite market fluctuations.