I'm not a Dublin cheerleader, I have just specificed that I don't use Dublin Airport for routes under 4,000 miles as it is 160 miles from my home and requires travel through the night.
Dublin for me, always works out cheaper because of the exchange rate and lower taxes. Business Class from Dublin goes for £1000-£1700 return, those same fares through Heathrow are £2500-£3,200.
This is a perfect example of the substantial savings in flying Long Haul from Dublin if necessary. There is also the added benefit of US Preclearance and zero backtracking that a traveller has to endure going from Heathrow.
Asia is only viable through Heathrow.