This is the exact script I use to install tailscale on my VPN server

Installing Tailscale

 curl -fsSL https://tailscale.com/install.sh | sh 

Enable IP forwarding

 echo 'net.ipv4.ip_forward = 1' | sudo tee -a /etc/sysctl.conf 
 echo 'net.ipv6.conf.all.forwarding = 1' | sudo tee -a /etc/sysctl.conf 
 sudo sysctl -p /etc/sysctl.conf 

Advertise subenets and exit node

 tailscale up --advertise-exit-node --advertise-routes=192.168.0.0/24,192.168.2.0/28,192.168.5.0/24,192.168.10.0/24

NUCs have an iGPU, you should be fine.

I use OpenMediaVault for my NAS

But if you don’t want to be the IT of your family, I’d just go with an easy solution like WDs my cloud or one drive

Encoding uses the iGPU. The iGPU should usually support 4k 60fps if it’s a recent CPU.

I’ve had this happen when I had ram issues. You can try doing a memory test if you want to take that out of the equation.

Adguard home

OpenMediaVault

JellyFin

I’ve bought about 600tb from server part deals.

Just got 20tb drives for about 250ish. Higher than what I wanted to pay, however $12.5/TB is good enough for me.