Frontend: Vue.js on top of Nuxt.js (reactive web programming cannot be easier than this and you get SSR or SPA or PWA or static page generation out of the box easily, you can decide later on that). There is not only React out there (which is like a jungle and more complicated in comparison to vue)...
Frontend styling and components: Vuetify or Bulma (you can also go with some vue bootstrap) + Stylus or SASS
Database: PostgreSQL (it's so stable, flexible e.g. with JSON, extendable and scalable in so many ways).
Backend: Whatever suits you to build a RESTful or GraphQL web API. Python+Flask, Go, Django, Ruby on Rails, Java Play Framework, PHP (e.g. Laravel) etc. etc.. Whatever you are most productive in. It does not matter really.
CI/CD and source control: Gitlab.com and the CI you get for free there is unbelievable good.
All of your points are great. Imo vue / nuxt is a much simpler and complete set compared to react and Gitlab CI is an amazing tool, you can literally use docker in docker to build the container right from it and even deploy to kubernetes.
Frontend: Vue.js on top of Nuxt.js (reactive web programming cannot be easier than this and you get SSR or SPA or PWA or static page generation out of the box easily, you can decide later on that). There is not only React out there (which is like a jungle and more complicated in comparison to vue)...
Frontend styling and components: Vuetify or Bulma (you can also go with some vue bootstrap) + Stylus or SASS
Database: PostgreSQL (it's so stable, flexible e.g. with JSON, extendable and scalable in so many ways).
Backend: Whatever suits you to build a RESTful or GraphQL web API. Python+Flask, Go, Django, Ruby on Rails, Java Play Framework, PHP (e.g. Laravel) etc. etc.. Whatever you are most productive in. It does not matter really.
CI/CD and source control: Gitlab.com and the CI you get for free there is unbelievable good.