Obviously this is your set, your design, etc. But did you consider using stock GMK colors? This looks an awful lot like 2B, N9, MG1 (magenta), CV (yellow), and TU2 (cyan). Going with stock colors gives you 100 less MOQ, meaning you can drop the price at 250 MOQ, or add more keys to the base kit, or leave more room for custom legends, etc. Plus using stock grays makes it easy to mix with other sets if you want.