I have a simple app, initialized by angular-cli.
It display some pages relative to 3 routes. I have 3 components. On one of this page I use lodash
I have a angular 5 + spring boot app(application.properties 1.3+) with help of compression(link attached below) was able to reduce the size of main.bundle.ts size from 2.7 MB to 530 KB.
Also by default --aot and --build-optimizer are enabled with --prod mode you need not specify those separately.
https://stackoverflow.com/a/28216983/9491345