After he becomes a US citizen, you will be considered an immediate relative and will not be subject to a priority date that was given to you. Just make sure your husband notifies CIS and the NVC of the fact that he naturalized.
just because someone is arrested it does not mean there will be an automatic ICE hold. What I would recommend is seeking advice from an experienced attorney as to whether anything can be done about his immigration status.
Do not take legal advice from a paralegal or a "notario", over the years I have see too many cases completely screwed up. Intent may certainly be a problem. I strongly suggest a personal consultation with an experienced attorney of your choice.
he will need to take care of the criminal and the immigration matter. Start looking for an experienced immigration attorney who can determine eligibility for relief from removal and work with the criminal attorney on the pending case.