Proposal for an open source/FOSS edition of ChromeOS:
-Fdroid and Aurora Store as the app stores
-Vivaldi as the default browser (specially made for ChromeOS)
-Google integration replaced with Nextcloud
-Search replaced with DuckDuckGo, Qwant, or a pre-customized SearXNG
-Play Services replaced with microG
-WINE integration (if possible)
Don't know what else to add actually but I would like some more ideas if possible! Also, this is just a concept