I have just booked direct flights from Heathrow to Manila, flying out on 23rd December and coming back on 13th January, so looking forward to Christmas and New Year in Vigan,
It cost around 780 which may be a little bit more than is available on non-direct (earlier this year i went with lufthansa for 450 to Hong Kong via Munich and then about 120 return HK to Manila, so about 570 total), but I ended up spending a chunk both ways on airport wi-fi, airport food, airport lounges, so taking all that into account this seems a great option.
I really hope this route is a success, and will be glad to share the experiences on here of course