Yup. The black Argyll seems to be the universally-agreed jacket to have if you can only have one. It is appropriate for nice daywear all the way up to certain levels of formality (see the "10 looks" thread for examples).

Once you've done that, you might also consider buying an inexpensive used tweed jacket on eBay or at a local resale shop, and having it converted to a kilt jacket for less casual daywear settings.