Rather unusually, I am going to chime in here as well. I happen to agree with every word that has been written here (actually I have been in Los Cabos during Spring Break - yes, I know what you mean). You still have not experienced a charter configured package holiday flight.
I will add this. I think that Iberia is not Europe's rudest airline, that accolade I give unreservedly to Alitalia. Him Indoors flew home from Fiumicino with them recently (we'd gone tch or some such). I understand that service offered a choice of meal (take it or leave it) and after a quick run - and it was that - the curtain was drawn so that the crew could get down to a serious bout of self admiration. This was Business Class.
The last time that I flew Iberia, I had no complaints on the outbound as the Purser was American and knew how to provide service. The return was the old school po-faced hoity-toity by-the-book old brigade. The answer to anything was "No", and the only seaving grace was the excellent lunch which was, sorry to say, far better than BA. The flights were punctual, and the airport (SVQ) was small and the gallician staff were charming.
Unfortunately, I think that this was the exception rather than the rule. Iberia is also highly unionised, and I can see that we will be flying and they will be grounded.
Overall, I think that codeshare is the biggest con ever pulled on the travelling public, and the only reason that it is tolerated is because of the possibilities of earning miles in your airline of choice. When you think of carriers like Swiss who were in the market, the choice of Iberia as a bedfellow is truly tacky, but I suppose they'd codeshare with Aeroflot these days.
If ever you fly with GB Airways, they ahve a Russian purser called Lubov (she talks like Marlene Dietrich) who was recruited from....Aeroflot. How she got a work permit beats me! (She happens to be first rate I would add).