I’m eligible for an Irish passport through my father, if I get one would I then be able to apply for wife / kids passports? Is having a passport enough to retire to somewhere in EU?
Don’t take this as gospel, as your father is Irish you can claim a passport, as your children’s grandfather at the time of their birth was Irish can also apply, If however you were using your grandfathers status, your children could not apply as their father or grandfather was NOT Irish at the time of their birth.
Your wife is AFAIK not entitled, but EU rules on spouses apply, and you would be ok everywhere apart from Ireland, though CTA covers most of that so no issue there.
On living in the EU you would be an Irish citizen, though there may be issues around healthcare, pensions and the like which I haven’t looked into. You wouldn’t have paid into the Irish system and this might have some bearing, Think EHIC cards, just because you have Irish citizenship doesn’t mean you can apply for an Irish EHIC.