This answer is very different depending upon your life circumstances.

A single person with fixed income, is different than a two income household with children. I'm not saying they can't both reach the same conclusion, just at their circumstances justify different choices being valid.

There's also your technical proficiency, and pain tolerance for saving money.

For example, you could eliminate all external services, self-host everything, and then configure an S3 object storage provider for critical cold storage backups. That might also require you spending a bit more upfront to expand your NAS storage capacity.

While that may save you a bunch of money in the long term, it will definitely cost you a lot of time and effort.

What's convenient for you? What can you not afford to lose access to? What's your budget? How much time do you have to manage different solutions?

Those aren't questions for you to provide me answers for, just some of the considerations that will impact different people's answer to this question.

I suggest enlarging your current NAS or building one and running something like Open Media Vault, Umbrel, CASA, etc.

For streaming, Kodi is the best value though it's via pirating. But is pirating such a bad thing when these companies steal your data and revoke movies that you purchased? With a debrid service costing $17 for 6mo you can stream basically anything with no slowdowns. Run Kodi via LibreElec on a RPi5.

Look into Plex. They are spinning their photos and music streaming into separate apps from video. PlexAMP is already out. You just have to set up a NAS or sever with port forwarding on your home network. I use an old spare PC as my server and it works great.

You can get everything under one brand with google.

Drive Photos Yt Music Yt tv

It’s designed to be device agnostic.

You can also do most of this with your Synology