If your looking to allow that kind of traffic in and out of opensense, then yes if you use it. Just be mindful of what you need and only allow that in, outbound is normally everything.
That's not container orchestration, that's infrastructure orchestration. Depending on your use case docker swarm could just the right tool for the job.
You've been using Aws and they will happily let you add more nodes to your container runner of choice
not sure I understand you, in docker swarm your containers are started on n number of works from a single compose file on a manager. you can add any number of work nodes to scale your service as needed
Some thing like this
iptables -I DOCKER-USER -m set --match-set ipsum src -j DROP
Should do what you need