The widthClass limits

Hi! Does anyone know a good solution when you have more widths than what widthClass 1–9 allows? I have 6 narrow widths (it’s a big range), for which tried and considered these options:

• widthClass = 0 seems to work, (which leaves 1 more width to solve). Any problems to expect?
• Negative and fractions don’t work
• I assume shifting Normal widthClass to 6 is not a good idea?
• I don’t quite like separating familyNames because it’s not going to be sorted in order either.
• Remove 1 width — not ideal.
• Set two narrowest widths to widthClass 0 and live with that ugly sorting.

Am I missing any better options?