I settled on Dashed-Account-Names, which work well for me because I can turn the dashes into spaces for display purposes but I don't have to be annoyed with quoting spaces at the command line.
The display usage is important for me because I share reports with other people. It's far friendlier to have lines like "Accounts Receivable: Dental Insurance Company" than, say, "accountsreceivable: dentalinsurancecompany".