Connectors are automatically routed. This includes routing around objects marked for avoidance. To mark an object that connectors should not cross:

To allow connectors to cross an object (the default), follow the above procedure but click the Ignore objects ( ) icon in the Tool Controls.

Connectors are automatically rerouted when either an object that the connector is attached to is moved or when objects that are marked to be avoided are modified.

The Tool Controls for the Connector Tool has an entry for Spacing. This adjusts the “padding” around objects that connectors must avoid.

The Align and Distribute dialog has a clickable icon ( ) for automatically rearranging connectors and connected objects in a “nice” arrangement. The placement is based on the Kamada-Kawai algorithm that treats the connectors as springs so that the distance between the connector handles are evenly spaced. Your mileage may vary.