Realistically, you should add a sub panel.

Otherwise, you cannot replace AFCI/GFCI breakers with non AFCI/GFCI tandems. I'm not even sure Eaton makes a tandem with AFCI/GFCI capabilities.

That said, I'm honestly surprised that having a separate breaker for your smoke alarms passed inspection. They should go on a common circuit so that way if the circuit trips, you know that your smokies aren't functional. A main lighting circuit is common. So, you could free up one space there if there isn't anything else of concern on that circuit.

You could also combine two bedrooms. Not sure if the entire bedroom (outlets and lighting) is on one circuit or what, but it's odd to have them separated that way. Are the bathrooms combined with the bedrooms completely? Or just the lights? Code doesn't allow for bathroom outlets to share with any other fixtures other than other bathrooms, and even then it is limited to counter top outlets only. Only way bathroom lights and counter top outlets can be on the same circuit is if that bathroom is the only thing on that circuit.

Additionally, you could combine the dishwasher and disposal into one circuit. I'm not a fan of it but as long as it's a 20A circuit, it's allowed.

If you decided to combine anything, you should really understand load balancing before doing so. Adding 60A to one side may or may not be a good idea.