User blog comment:Rupert Giles/Layout Changes: Breakpoints and Typography/@comment-1820055-20150520085207

why not release a duplicate skin with this mixed in, and one without, where people can still choose what they prefer?

iirc you can still choose a preferred skin on your Special:Preferences where you can choose Wikia vs MonoBook.. why not just add this to the choices, i.e. WikiaMobile or something?

and it would help if we can choose which is the default layout for our users per wiki..

IMHO this is a solution which can save you long-term in case you want to implement more drastic features and changes, where you can see a significant reduction on community rage, coz you give them what they want, freedom. I've seen that terminology a bit throughout the updates.