Is there anyway to link to

actual

declarations via a gutter icon as of yet for expect/actual usages, or any plans to add this feature for KMP projects?

Currently, you can navigate to expect/actuals using the code vision elements above the declarations, if you have the “Show code interlines” setting turned on

Thanks. Any plans to expand options for what can be be done in the gutter?

There's a bug tracking this here https://youtrack.jetbrains.com/issue/FL-12285/Find-places-for-gutter-icons-from-IntelliJ