At least in my version of Luminate, when I try to add a divider line to my email body, it defaults to lime green and dashed. I really can't think of an instance where those would be the most common/desired features of a divider line in a fundraising email. Can you change it to 3px light gray solid line or something similarly usable off the bat? I know it's low-hanging fruit - but that is even more so why I would also expect it to be a quick, email-ready email component for your users.