An isomorphic framework is just what you need for indexing. By rendering pages on the server side, the search engines will see everything you need. Furthermore, modern search engines quite a learning SPA sites here, such as the Yandex tells how to do it
. Google prefers Progressive enhancement
Why do you need? Then, the website was the app (exactly the same as on smartphones and other devices). In situations where your product is not only a website, but also a bunch of other devices, this will allow you to simplify the server part. 1 server and Rest API for all, instead of doing a separate website with its own server, and a separate infrastructure for mobile apps.