Just keep in mind, if you intend to use Google Messages (the only current way to get encrypted RCS messages), it only works on the Owner profile and it requires play services among other permissions and workarounds (see the mighty infamous RCS discussion thread on here).
While other message platforms have more privacy benefits, RCS is still better than SMS as it's encrypted between others Google messages users and is expected to be encrypted between Apple iMessage users soon, both of which are the default message clients for android and iphone respectively. Americans especially (land of the iMessage obsessed) should strongly consider making sure RCS works on their phone as a stopgap for the majority of people that refuse to use anything other than their phone's default messenger.
Push notifications also for the most part require play services, even for privacy respecting apps like Proton Mail and Signal. So if you want real time notifications for these sorts of things, you kinda still need play services installed on your main profile or you'll need to keep multiple profiles running at the same time, which can kill battery life.
While some apps can provide push notifications without play services, the mechanism through which they do it is less battery efficient.
Running a profile with Play services compared to a profile without play services & no push notifications will be worse for battery life, but for most people, this would be considered an unusable device. People usually want to be notified in real time for things..that's one of the selling points for always carrying these things around with us.
Meanwhile, allowing even just 1 app to provide its own push notifications without play services (such as how Signal and Molly do it) would still be worse for battery than running sandboxed play services handling push notifications for all of your apps.
Just things to consider. Privacy fatigue is a thing, which is why people often recommend to new users a simple setup where things just work.