Nero (black) and Ebano (brown) are classic colors and are not included in the sales although exceptions might be if a style is being discontinued. I think Ardoise (charcoal gray) and Tourmaline (very dark blue) are also considered classic (or permanent) colors now. During this sale, I wanted something in Prusse Blue or Light Tourmaline but was told these colors were not included because they are semi-permanent colors.
For me, black is almost always a great color to start with.
I really think classic is in the eye of the beholder. One might think there's nothing more classic than a great red bag. I got a New Sand Bella bag and my sister said its one of the most elegant and classic colors she's ever seen. I would focus more on what color works for you and a color that you nine you'd wear for many years.
If you're asking purely in terms of BVs collection, a general rule of thumb is that if it's bright, pale or jewel toned, it's probably a seasonal color. The dark more neutral tones tend to be BVs permanent colors.