We'll be flying Aer Lingus to Venice via Dublin next May, with 2 hours between flights each way. Last year, we also flew Aer Lingus to London, with a bit less than two hours for connections. Our flights arrived on time in Dublin and we had PLENTY of time. An hour should be fine as long as your arrival flight is close to on time.
If we would have been delayed arriving in Dublin last year, there would have been multiple flights to London the same day, so worst case is we would have arrived there a bit later in the day.
After booking our trip for next May, I realized that Aer Lingus has only one flight per day to Venice. So if something happens to delay us, we're stuck in Dublin for the day. And that's how I'm approaching it. The worst that happens is we're stuck in Dublin for the day, so let's make the most of it. We'll see a little less of Venice and cut it a little close arriving for our RS tour, but we'll get a totally different experience while shaking off our jet lag in Dublin. In other words, I'm determined to roll with it if things don't go totally according to plan.