Warn on Master/Detail deployment even without comparing Custom Fields
If you compare Custom Fields and try to deploy something in an Object that is in a Master/Detail relationship without including the Lookup field, Gearset will warn you that the deployment will fail.
However, if you don't include "Custom Fields" in the comparison, (for example just comparing Validations) and try to push it, you will hit an error:
"Cannot set sharingModel to ControlledByParent on a CustomObject without a MasterDetail relationship field"
Gearset could easily warn the user on this when trying to push a Validation Rule on a MasterDetail object, even if Custom Field was not added to the comparison.