Thanks for the many feedback folks.

- No, I will be flying economy so no lounge access. It's a work trip.
- I checked and the layover at LHR will be at T2, both arrival and departure.
- LHR layover will be between 1.5 to 2 hours, based on the flight choices I'm allowed
- All connecting flights to Dublin from layover will be with Aer Lingus.

Looks like most people prefer AMS or MUC. Although at this point unlikely, if I can swing a stopover, my preference will be AMS since I've never been there before.