Configurable Google Analytics tracking code only, no UI in WordPress. Too many plugins seem to have tracking code that is only vaguely configurable in WordPress, maybe because they focus so intensely on providing dashboards for users to see inside WordPress.
We don't need any of those dashboards, but we do need to be able to configure custom dimensions, particularly based on our own code that is in other plugins, so we need to have a number of developer hooks that other plugins don't seem to provide, at least not without paying a subscription fee.