This is a good question! We had been on cruise pre-pandemic (on Azura, to Norway). We love Norway so quite happy to have gone on more or less the same itinerary multiple times now, although actually we’ve been to one previously unvisited port on each trip so there’s a tiny bit of variety!
The Med on Arvia next year will be a change for us: I’m not sure how often I feel that itinerary will bear repeating: I guess I’ll have a better idea once we have done it once.
At this stage in our lives repetitiveness is a positive boon - we have stressful busy jobs and a young autistic child so knowing what to expect is actively helpful! I doubt we will feel that way forever and as our daughter gets older I think we will want to spread our wings a bit. I do wish that there was a bit more variation in what P&O offer.
In terms of why we like the ships: I like that Iona (and I assume Arvia) feel very modern and not dated. I also like that standard balcony cabins all have sofa beds - I’m not keen on Pullman beds or having to sleep in separated singles to accommodate the pull down beds so it’s a bonus not to have to shell out extra for a deluxe cabin to get that. I like that there is a wider choice of places to eat than on the smaller ships. I like the massive windows in the atrium!
Ultimately for us P&O offer a good value proposition, and the opportunity for a nice holiday abroad without flying and with relatively little hassle. I’d happily try other cruise lines but they all seem a lot more like expensive, and at the moment we’re happy with the product we get for the price we pay.