I use Eclipse and Netbeans of free will.

Saying this as probably the biggest Java fanboy I know: they are pretty bad. Gradle is pretty much the worst build system Ive used. IntelliJ might as well be folded into the JDK, because I don't think it's possible to be productive in Java without it.

Everything you said applies to Kotlin as well. Outside of IntelliJ, it is horrible to use. (Ditto Swift outside of Xcode.)