I can relate to not wanting any of the tech giants near my shit but may I ask what your Google concerns are on GrapheneOS?
I also have an iPhone as well as a GrapheneOS phone. They are different but I'm quite happy with those alternatives to the apps you mentioned:
Etar as a calendar frontend app. DAVx5 for syncing CalDAV and CardDAV (so calendar data, contacts and optionally also tasks). I manage tasks within my notes, so I do not really use a todo/reminder app at all but there are different options. tasks.org plugs into DAVx5, for example.
Depending on your server-side setup and your willingness to compromise on open source, are also other options. For example, if you work with an Exchange server, there is the "Nine - Email & Calendar" app which is a very powerful all-in-one-client similar to traditional Outlook on the desktop.
For photos, there are quite a few solid options, depending on what you want. I use the Fossify Gallery with only my Camera folder visible for day-to-day stuff and also have Aves Libre installed for a more advanced interface to my pictures and videos.
Interesting. Can I ask if you use Apple's cloud services? If so, I understand. I don't use those, even on Apple devices, so to me, the whole setup is similarly annoying on both platforms with maybe a very slight edge towards the iPhone because it has most things I need out of the box. Other than that, I really don't think I miss anything on the "basic stuff" front on my Pixel compared to my iPhone (I use them both daily, with the former being my personal phone and the latter the job-issued one).
I've been doing the dual-driving iPhones and Android devices for a long time and times were definitely worse, in my opinion. The last thing I remember really annoying me on the regular was the lack of AirDrop but with alternatives like LocalSend and KDE connect, that's fixed as well.
I'm using AdGuard for blocking ads in Safari. Works fine.
I do have a GrapheneOS pixel 7a as well but I'd rather not let Google near my shit.