What if RDE's green and red Add/Delete buttons were on the left side of the lines (where the error indicators currently are in the screen shot)? This way, it would be easier for users to delete lines instead of having to scroll all the way to the right side. This would also mean the two green Add Row buttons above and below wouldn't necessarily need to be there. Also, what if clicking Add a line between existing line could insert a line like in Excel? There have been many times when I'm entering in an inventory that I've wished for this function.
Moving the +/- buttons to the left was echoed by this ticket, which was closed as a duplicate: https://archivesspace.atlassian.net/browse/ANW-103 "Users report that they weren't even aware of them."