I thought Westerdam was in quite good shape and nothing said tired or worn out. I was very pleased with it's condition and the crew moral was very high. A very good cruise experience.
We did half the touring on our own and took HAL tours in Costa Rica (mangrove boat tour), Guatemala (Antigua on your own) and Caragena (Cartagena walking tour). In Cabo, Acapulco, Huatulco, Puerto Quetzal we did our own thing.
Be very honest about yourself when you choose what you want to do! Make sure you know that you are going to 3rd world countries in the tropics. They have two seasons: hot & wet and hotter & wetter. You will get hot and sweaty and you will see poverty (not Africa poverty, but still disturbing to some Americans).
As for recommending any shore excursions it really depends on what you want to do and how active you are. For example the Cartagena walking tour is listed as strenuous with plenty of warning about walking up inclines and on cobblestone/brick streets. I would call it very slow, relaxed walking with a break every 5 minutes and the longest we ever went without a sit down break was 30 minutes. Still many people complained constantly that it was too strenuous and hot.
Are you active? (do you use the stairs on the ship or are you an elevator person)
How adventuresome are you? (do you like being in a group of other ship passengers with an English speaking guide, or are you comfortable to explore on your own in an area where the people look different than you)
Do you want to see the real place you are visiting or do you want something more staged and prepared for an American tourist? (do you like to try the local food or do you want a zip line or see a staged dancing act)