I would like to propose the following changes to Wall attachment behavior:
1. Wall height to reflect the current\actual current height. Currently, it shows wall height PRIOR to attachment.
2. Add an indicator in the instance properties window about the wall being currently attached.
3. When attachment conditions no longer physically possible, leave wall height as is, IF changing current height leads to hosted elements getting deleted.
4. When attachment conditions no longer physically possible, automatically remove attachment and joined geometry conditions, instead of generating unnecessary warning.