Nice hand list of utilities and services. I've been on the fence about start 9 for a while thinking if I should building or buying.
Privacy or descentralized alternatives you may need:
Non KYC Bitcoin https://hodlhodl.com/
Cold storage https://coldcard.com/
Keep safe your seed stampseed.com/
Spend your sats bitrefill.com
Mobile grapheneos.org/
Node start9.com/
Private App signal.org
Private email proton.me
Private browser brave.com
VPN mullvad.net
NextCloud - nextcloud.com
OnionShare - docs.onionshare.org
Tutanota - tuta.com
Bitwarden - bitwarden.com
Quad9 - quad9.net/es/
Yubikey - yubico.com
F-Droid - f-droid.org
Jellyfin - jellyfin.org
Calibre - calibre-ebook.com
GIMP - gimp.org
Veracrypt - veracrypt.fr
Shotcut - shotcut.org
That's all.
Discussion
Start9 is very simple for the fact that you already have everything ready to download.
There are even more user-friendly options like Umbrell, but it's not too focused on privacy.
If you want to learn the whole process you can start with a raspberry pi4 or 5, although it won't be a big change either. Anyway if you want to do it all yourself, I recommend you take a look at these two websites:
https://darthcoin.substack.com/p/bitcoin-private-banks-over-lightning
https://minibolt.minibolt.info/bonus-guides/bitcoin
If you have any question just ask. I will be glad to help you :)