I decided to move my contacts to Baikal because you inspired me, and because of current situation in the world. I wanted at least contacts to be more private...
When it comes to nextcloud I playing with that idea for longer time, but last when i tried selfhosted it, it ended with fiasco..Currently testing hetzner hosted cloud, but find that also kDireve from infomaniak exists and it is cheaper... Why did you not considering this? (this is not ads and im not afiliated with them, currently have one from big tech cloud)
And when it comes to privacy i still trying to figure out why people consider this they use instead of their alternatives... When it was me ill go with Proton, or something but it is expensive and see that not very much privacy oriented people using them (at leas those I follow in RSS)...