On the point of Paris nobody seems to be able to make that one work long term. I wonder are the aircraft too big for such routes?
From this side of the Celtic Sea, the problem is Paris - no-one beyond Paris wants to go there, to the point that SNCF have this week cut Paris-Province services by around 25%. Neither does the local "central France" population particularly want to go to Dublin. Bord Fáilte has done a great job - in the minds of the non-Parisian French, the only part of Ireland really worth visiting is the West - but it's marginally quicker and significantly cheaper to get there by road and sea than by any of the currently available air routes. Paris is a novelty, and novelties wear off.