Why are we making this software? Who is the customer?
We now know why we are making software, let's find out how it should look!
Develop the software with the appropriate technologies! (usually proven and "boring" technologies)
High quality software requires testing, not only during development, but automated tests running in a continuous development pipeline to avoid regressions.
AWS, Azure or GCP? The biggest cloud vendors are often the correct choice, but not always. Whatever the platform to deploy, using infrastructure as code, automate and avoid excessive resource usage to keep cost low is important.
All software becomes "legacy". Without care, it can becoem unmaintainable. The maintenance phase is as important as the development phase, ensuring longevity of the software.