It would be great to add both internal and/or external notes to individual line items. For example as an internal note; 'camera location to be confirmed on site' or '4x rows of 3 speakers, zoned for voice lift'. Or even during quoting 'Check compatibility of this item with X' or 'Check cable distance for X extender' etc. These notes can be used whilst putting the proposals together at 'quick glance', and can flow on into the project and delivery stage. There are many applications where this would be useful for internal and external (client facing) notes on line items, however I think internal notes would be a priority.