Ireland 14 Days by Rail - tips/tricks/advice

Think train and bus for the most effective trip.

Perhaps you have a specific tour or guide in mind for the Ring of Kerry and Dingle Peninsula tours but it seems odd to me to take it from Cork. I think it would make more sense to use Killarney as your base for Kerry and Dingle. Killarney is on the RIng of Kerry and much closer to the Dingle Peninsula than Cork.

While the Irish rail system is pretty good, there are large swaths of the country where it just does not go (including lots of places you want to go). Furthermore, to get from some places to others by rail often requires "doubling back" a long, long way. Much of your trip would be so much more efficient with a private car or other means. Have a look at the system map:

Irish Rail Intercity Rail Map

Plan to drop off your laundry at a “fluff & fold” laundry service.

As was mentioned, relying on the train system will necessitate a lot of doubling back on yourself (and a lot of wasted time) since it's basically a hub and spoke system centered in Dublin.
Might help to streamline things a bit if you take advantage of the relatively cheap flights between Dublin and the Kerry airport near Killarney. RyanAir runs two flights per day between the two, and if either of the ongoing flights meshes with your arrival time at Dublin you could head directly to Killarney, begin your explorations from there, then return to Dublin via RyanAir when you're done - would save you a lot of time versus riding the rails. From Dublin it's a short 2 hour train ride to Galway or up to Belfast.
Personal opinion only, but we've always been pretty underwhelmed by Cork so scrubbing that from your itinerary wouldn't be any great loss. Better (I think) to take the extra couple of days and apply them elsewhere on your journey.