Holland America Line (HAL) prides itself of being a "signature of excellence". That is far from being true in our experience. If I had to grade them, a "C" would be a fair grade.
Certainly, you will find high quality food and an attractive international atmosphere, but there're aspects where HAL needs clear improvements, especially during Summer cruises. If you're travelling with children, you may want to consider other alternatives such as Royal Caribbean or NCL (Norwegian).
A few examples of why HAL would be a "C" and not an "A+":
1. Hygiene at the swimming-pools: renewing the water of the swimming pools once-a-week in October in a Nordic cruise with senior passengers may be a good procedure. Doing the same in a 2.400 crowded August cruise with 250 children on board seems inadequate. One afternoon, one of the swimming pools had even to be closed due to a hygienic incident (one child pooped in the swimming pool). Chemical treatment of the water is not the solution. Water should be filtered continuously and changed far more often (eg. NCL changes the water everyday). Neither my wife nor myself used the swimming pools during the last 6 days of cruise, once we were informed by Holland personnel about the procedures of changing water in the swimming pools.
2. Service: we experienced very slow service in the main restaurants, Lido and Manhattan. Most evenings it took us more than 1 to have dinner, with waiting times of more than 20 minutes between courses. Even in the Pinnacle restaurant (the most luxurious) we had that waiting time, which was a pity because the food had been excellent. I think that might be due to the fact that the ship navigated with a much higher number of people than the capacity shown in Holland brochures (2.104 passengers according to the brochures vs. 2.400 people in our trip according to the cruise director). This is, around 20% more than in regular trips according to the brochures, when some infrastructures of the ship are designed for a minor number of people. Was the personnel also increased by 20%? It didn't look so.
3. Entertainment/shows: high-quality but lack of variety and with not enough shows family-oriented. If I recall correctly, six of the shows were done by the same group of musicians and dancers (very good, but six times seems too much). Another three were also musical-based shows (piano, and violin). Only one was different (a magician). As a result, our children quit attending the shows the third night of the cruise.
Additionally to this, we made a complaint at the front desk about the procedures followed by Holland during the tenders (in Nafplion). First of all, we were surprised that there was a "tender" disembarkation in Nafplion. We reviewed the brochures we had (from our travel agency and the specific of the tour operator), as well as Holland America check-in information and itinerary. None of these documents mentioned the tender at Nafplion.
Also, none of the documents mentioned any variation of the disembarkation time depending on the category of the stateroom, nor depending of having contracted or not an excursion with Holland.
Quite frankly, we felt discriminated by this procedure. Many other passengers felt the same.
We think it would have been easy to make compatible the plans of those passengers with Holland-contracted excursions with the vacations plans of those who travel independently. For example, 4 of the 8 excursions planned by Holland in Nafplion had a 4-hour duration, and they could have been planned in advance for a latter disembarkation.
Summing up, we didn't consider acceptable to discriminate passengers on this matter based on the products contracted with Holland. We made a complaint at the front desk about this issue and crossed one e-mail with a HAL representative, until we got no further answer. I guess there're some things difficult to explain...