Free and Open Source Software

For me, the key aspects for selecting the right hardware are the camera and the comunity support. All the other capabillities you listed are available on any phone that has a relatively recent ROM available.

Let's start with the camera quality: If you want to use your phone without GSF or microG, you could use the camera app that comes with the ROM you flashed. Sometimes, the picture quallity is decent, but often times its lacking. Instead, I would recommend using a modded GCam App together with fake GSF. This way, you can use googles powerful camera app without sacrificing your privacy. So when I'm looking for hardware, I always check, if there is a modded GCam version available.

Aside from that, I would check if there are recent stable versions of the ROM I want, available for the hardware. The last thing I would check is, how active and how big the modding community for that device is. If you can't find a lot of support on XDA, it's probably not the best hardware choice to begin with.

When it comes to software, there are a lot of privacy-friendly replacements to choose from, but here is my setup:

• Syncing Contacts and Todos: selfhosted baikal + DavX5 + Simple Contacts + Tasks
• Syncing Photos: selfhosted NextCloud AIO + nextcloud app
• Syncing Notes: selfhosted webdav + Joplin
• Find My Phone functionality: FindMyDevice
• Maps: OrganicMaps
• Speach to text: FUTO Voice
• Synced Music: Selfhosted JellyFin + FinAmp
• browser bookmark sync: selfhosted webdav + floccus

EDIT: GCam and FUTO are not Open Source, but they are free and don't collect or require any user data