New user ranking and posting restriction

We have been torn about whether new users should be able to post or not without requiring moderation. Right now all users are set at level 0.

In certain categories, we dont see problematic posts. Its primarily a few controversial categories, or users who have other names associated with their IP, who try to agitate the community.

Just wondering if there could be ways to change the min user level for new topic by category. And/or be able to set a different user level (level 1) if no other previous accounts can be found for the newly registered user (based on ip or browser cookie)