Do you have any plan to improve it's scalability?

I have one answer. The choice of technology depends only on your project, and on its nature. If scalability is not planned, but in certain volumes, and it takes a lot of resources, then the VSAN https://www.starwindsoftware.com/starwind-virtual-san architecture can be used. It is able to combine computing and storage functions in a server. This approach will allow you to scale quickly and cost-effectively. The service of Virtual SAN available for you by providers, where you rent this resource.

What resources can be used to ensure the scalability of the project, especially when it comes to different business concepts? What storage solutions do you think are possible?

A couple of years ago Adobe was excited about AEM in the cloud SaaS, but this offering seems to have quietly gone away. We use AEM at Rackspace where we have the ability to scale both horizontally and vertically at the touch of a button. We also utilize both AWS and the Rackspace Cloud and have written automation that will automatically scale up our AEM implementation when it is under high load and shrink it when it traffic slows.