This post explains it: How to help with missing/broken cities/regions
There’s a Google Sheet where I collect this info. You don’t have to be thorough about the extra fields … I do need city/region/country and the OSM link, but the extra fields indicating the problem, whether it’s fixed, etc you can skip.
I think the biggest thing to be aware of is whether the CDPs/areas you’re proposing have any overlap with existing cities in CityStrides.