john lennon is a new and efficient airport. ryanair are usually pretty good on punctuality I think you will be ok. ps ryanair have direct flights on tues , thurs and sats to fuert. best deals seem to be around the tues/satys ones, for some odd reason the thurs ones are usually more expensive.
Ryan air only have Sat flights direct from Shannon and Hubby refuses to travel through Dublin if possible. (Not just the airport, traffic, length of journey etc makes him very irritable, so not a good start to holiday.)