It depends on what you want out of your phone. I use Calyx because I like living a foss-as-much-as-possible lifestyle, and they've got some pretty cool networking features (sharing VPN over hotspot and across profiles) and I prefer to use MicroG over sandboxed play services. Muerena is kind of for people who want an iOS-like experience without the spying. Ive never actually tried iode myself. Lineage is kind of the base starting point. Its available for a lot more phones than Calyx and Graphene support (You can even install it on some Nintendo Switches!), but its not as Privacy hardened. UBTouch & Postmarket OS are for the brave souls who want to give linux mobile a go. I want to try it one day but I want to use KDE Plasma Mobile instead of Ubuntu Touch. PostmarketOS afaik is the furthest along mobile linux OS with KDE Plasma Mobile, but the phone I would want it on has broken audio drivers ATM so its a no go for me rn.
Give them all a look though, look into threat modeling and what features you might want. You may find Graphene works just fine for you, you may find another project suits your needs a lot more. Its hard to really say one way or another! :P
I dont think defeating fascism involves platforming the fascists.