As you say the 380 has it's own jetway in F so boarding is fairly easy, there may still be a line at the priority queue though if you miss group 1 as those with status and busiess can also use this line but once your BP is scanned you have your own airbridge.
I aim to be at the gate for 40 minutes on longhaul, I'd tend to leave the lounge 60 mins before departure and walk through the tunnels rather than take the train.