Springboot (you can see for "jhipster" for a quick start with spring/angularJs ) is used in many micro service enterprise applications (they are design for), so API integration is "as easy as ABC". With this you can scale and give an answer to some of your questions: performance, speed, reliability and security. But be carefull with the learning curve...

NB:

• For the DB, leave mysql and go to Postgres! their is no other option! you say thank you later! (a nosql database can be a nice tool too)
• You have associated a front framework with a back framework, but they is no good reason to do that. You can use vuejs with springboot too (and i use them!)