Aruba is a small island, in 30 minutes (mid-low speed) you can drive from one coast to the other. It is very safe, probably the safest place I have been in my adult life. Activities are mainly in the tourist area, but on Thursday evening there is this weekly happening going on called "Carubbian festival". It's in San Nicolas from 6-10PM. I'd suggest to come at 5PM if you want to have a seat while enjoying local food. The event is actually quite nice with both local people and tourists.
I stayed there for a month, because I was exploring my options to live there. For a holiday I think 1 max 2 weeks is long enough. Aruba is very Americanized as (Northern)Americans are the main target group.
The real Aruban culture is not as outspoken as you might see in other countries/islands, e.g. local markets, picturesque towns, nature's wonders. The pros of Aruba are safety, stable weather, amazing seawater and nice beaches, very friendly and elegant people. Life is easy.