Cancelling credit cards when switching banks.

I recently moved across the country and will be getting married in September. My fiancé and I will be getting a joint bank account and can't be with the credit union I was with where I used to live. I have a credit card with my credit union. There are no perks or cash back rewards that come with it so there's no real incentive to use it or keep it when switching to a new credit union. So is it okay to just cancel that card when I close my account and get a new one, preferably one with perks/rewards. I've heard closing credit card accounts can negatively effect your credit so should I keep this one open and just get a new one or cancel it and not have multiple credit card accounts? What would be my best option or way to deal with it?