If Gonzales gets nominated, oh boy. We're in trouble. He's the guy that thought up the brilliant idea to attempt to gut the Geneva Convention, using Gitmo to store any prisoners without civilian court oversight, the "coercive interrogation" thing, exemptions to the US Code Title 18 Chapter 118 Section 2441 (war crimes statute), etc etc. Mind you, he has not just applied these to "unlawful combatants" but also US citizens. Ask Padilla. Gonzales also spends a healthy amount of time trying to expand the PATRIOT Act and other liberty gutting legislation. Etc etc.
Sorry, anyone that actively supports arresting US citizens and holding them indefinitely without trial should never even be considered for the Supreme Court.
To keep it RKBA, Gonzales has not shown himself to be exactly pro-RKBA. At best, he's more interested in simply maintaining the status quo. This is not bad, of course, but it's not exactly good either. His singular pro-RKBA measure was stating that the 2A is an individual right.
With a stroke of the pen, Gonzales could effectively put the ATF in a cage. More favorable definitions of "sporting purpose", removing 7.62x39mm from the armor piercing pistol round catagory (not sure the official terminology, basically the steel core 7.62), and dozens of other pro-RKBA measures. Small things individually, but they'd add up.