Even if England/Britain doesn't take control of Ireland, the presence of such a larger, wealthier neighbour is inevitably going to see English become widely used although it wouldn't supplant Gaelic as the
de facto as opposed to
de jure first language. Ireland would probably be more Anglophile today as without the colonial legacy things like football wouldn't have the stigma of being "foreign games," so there would be more everyday use of Gaelic but Dublin Airport would still be crowded most Saturday mornings with football fans heading to England for the day!
The idea of Spanish or French colonialism is really interesting, I guess that having Catholic overlords would remove the religious conflict which was what really drove a wedge between Britain and Ireland. If the Spanish/French proved as bad as the British did or trying to impose their culture on the Irish then I imagine there will be a violent reaction at some point.