We do have the option to change some defaults as part of Declarative Gradle.

withJavadoc/withSources this should be the default

I agree.

test suits should throw an error if no tests are present

Possibly. What problem are you aiming to solve with this? That someone has registered a test suite but put the source files in the wrong place? Something else?

test suites should be more verbose by default

What would you like to see here? Some more information on the console? Something more in the IDE or reports or scans?

prerelease's aren't expected by anyone as a default,

I'm not sure what this means. Do you mean that dependency resolution is choosing pre-released versions rather than released versions in some cases?