If you add gorm, groovy, and are building json api's - MN feels almost the same as Grails - also you dont have to use reactive programming either if you dont want to (i dont). Grails 4 has a MN parent context - I've been playing with moving some things there - eg services. If you need GSPs, or spring-specific things it's a good reason to stay with grails. I also miss json views (instead of creating tons of pojo's for json)