Those people are going to be miserable no matter what, and they just want the site to be like their own personal cool kids club since before the newfags arrived the year after they did. I don't think you can please these people, and I'm honestly not sure why you'd listen to their requests in good faith and unban troublemakers like APC and Sig on their suggestion. They obviously just want those people around to cause chaos.
Unbanning Sig was a bad move because he unquestionably did something that put the site at risk. Frankly it just appears as though you caved to peer pressure to let him back in. He repaid that hospitality by turning around and shilling his breakaway site at every opportunity.