Paul Norman has just announced new vector style called Bolder:

https://www.openstreetmap.org/user/pnorman/diary/43814
https://github.com/pnorman/bolder

It is a candidate for osm-carto migration, but there are still many moving parts, so expect no immediate results.

[UPDATE:] Bolder is unrelated to osm-carto vector migration. It’s just a new, client-side vector style using the same database schema as osm-carto.