Aer Ryan - given that the following routes have all failed I'm not sure I share your optimism that FR operating PIK-SNN again is the answer...
EDI-SNN - Ryanair
EDI-SNN - Aer Lingus
GLA-SNN - Flybe
GLA-SNN - Aer Lingus
PIK-SNN - Ryanair
IF it was that popular a route surely one of the above would be operating it this summer. I remember being on PIK-SNN a few times back around 2006/2007 and there were often only 60 or 70 people on board with flight prices at about £10 return. That didn't work back then and it won't work now either. Many, including myself, that were on the edge of Shannon's catchment area back then wouldn't bother with the place now with the M6 offering much easier access to Dublin from the west coast - so if anything the demand is even less now and operational costs would be higher.
Ryanair might maybe just about manage to successfully operate EDI-SNN again three times as week if Shannon management let them use their airport for free or maybe even pay them a few quid to land there. That's about as much as can be sustained on Shannon to Scotland routes at this stage.
In terms of the topic of the thread, Ryanair don't fly from PIK to Ireland any more.