I agree on the lounge, and it's eerie seeing Dublin airport so quiet! Although it doesn't take anytime to get through the airport make sure to check the published last check in time, as its quieter they may just shut up check in exactly to the book - you don't want to be caught out!
It's a lighter load flight anyway, or at least any time I've been on it - though just remembered you're in First, so that really doesn't matter
Enjoy!