Your problem is that you don't have a termination criterion, so I propose this: 1. Write the product and tech specs. This lets you know when your work is done.

Your problem is that you don't have a termination criterion, so I propose this: 1. Write the product and tech specs. This lets you know when your work is done. 2. Propose an architecture that meets it, and move on. Don't overengineer it. 3. Implement the architecture.