We are at about 92% unrestricted and have to be careful not to let the perfect be the enemy of the good. (good in relative terms, only)
One thing we almost got was real judicial review, but someone pulled the magic two words "de novo" out of the last gun control bill before it became law. If that had to survive, judges would have to examine facts and justify their decision rather than conclude "The court agrees the issuing authority thought he had a valid reason" that passes for review now.
And then there is the moving standard. It was changed from "suitable" to suitable based on danger to self or others. The courts ignore that and still use the old "any reason" standard.
Standard of evidence in license review is another target - the law should specifically hold licensing review to the same standard as other hearings, and undo precedent that establishes that things like not-guilty findings, hearesay evidence, etc. can be used. This is most interesting considering there seems to be a movement allowing multiple complaints against an LEO to be used against him/her, even if each individual one was unfounded. We,, I say "welcome to the club".