I'm in the same position as you, although I'm pretty sure we'll never be able to transition our ERP wannabe fully into a SPA, and that's why I'll likely choose Vue for the frontend and Laravel for the bulk of the backend and middleware architecture (because we own legacy PHP code)—with the idea that if it comes to a point we wanna separate the monolith's backend into microservices or just opportunistically spin of some of it into microservices it will be relatively easy to just plug in Lumen for that. What we'll try to achieve is: have multiple SPA-like views for various modules and and have those share components on the front-end and a MySQL based data loosely modelled as MVC that orchestrates our fairly large scoped app. The reason I choose Vue is because it has lower learning curve and lower barrier of entry for devs that know vanilla javascript. I would have liked to be able to choose native web components with a light glue/helper framework (basically Polymer) but unfortunately the tech is not mature enough and has too many unknowns for me to invest in it, but I hope I can leverage Vue to build components using custom elements at the very least. Aurelia and React seemed nice also but I wasn't sure they'd fit as they are more opinionated either from an architectural standpoint (Aurelia) or from a technological standpoint (React). Also Aurelia I'm not sure that it has a good enough ecosystem for now—but that's likely to change—and I'd be inclined to choose that over React at that point because it tries less to reinvent javascript (and web technologies) and more to build abstractions on top of it. This are just opinions of course and should not be read literally because I do understand that there are nuances regarding these frameworks.