Your suggestion for allowing a percentage of 0.0 to have 1 player sleep to skip the night has been implemented in the latest version (0.5.1).
The next update (0.6.0) will build on this and incorporate @Keuterio’s idea for allowing other specified amounts (e.g. 5, 10, or any integer value). It will be available as a new configuration option, and the plugin will pick the smaller of the two requirements.