[Vuejs]-Packing all dynamic data into a single Vuex store

As mentioned in the comments, Vuex is meant to manage complexity and in your case you are planning to fetch 99% of the data at the beginning for your app. So, in client-server aspect, you totally don’t need it. Keeping your data structured would be enough.

However, you have also the notion mutation in Vuex. The idea is that you can update the core data only using mutations. In this way, you are protected from unwanted changes and you have a better insight how/in which order your data is changing. So, if you have complex operations on your data (fetched from server and also your apps logic), Vuex would be a good choice.

There are also another interesting features for different kind of apps. Note that is just another trending way to keep your data structured. There are also another strategies but since Vuex is regularly maintained by Vue core team (and it seems to be also in the future), I would suggest it. Especially, if your app keep growing, you will love it more and more. After reading core concepts of Vuex (or better its logic behind Vuex: FLUX), you will have better insight about it.