It wouldn't be so bad if it was a member of the peace movement. Might even be good company.
So basically:
During the war, I wouldn't have been voluntary, but I'd try to negociate with my Yeerk to join the peace movement. If he agreed, I'd become voluntary. If he didn't agree, and continued to try and break me, then I'd fight him.
After the war, I imagine that the Yeerks were allowed to keep their voluntary hosts, and anyone willing to become hosts could do so, and have special conditions. If the Yeerk didn't agree to those conditions, then too bad, no host for you! In that case, I'd be a voluntary on the condition that I could stay on Earth, and have control when I'm with my loved ones.