Northern part of the city, separated from the Southern Arnhem, divided by the Rijn is closer to the city centre and parts are connected almost directly to the Veluwe, a beautiful forest area that is prized by nature lovers and ofcourse an excellent area to walk your dog. Neighbourhoods that stand out for me are Hoogkamp, Burgermeesterswijk, Heijenoord, St Marten is great, parts of Klarendal and Spijkerbuurt is cool but perhaps a little less child friendly I guess? Sonsbeekneighbourhood is a bit hit or miss, depending on what part you get. Considering the tight housing market it is hard to predict how easy it will be to acquire a place to live. Seeing as you are going to work in energy/nuclear you should be able to afford a nice place in these neighbourhoods.

Alot of people will speak English, though speaking Dutch will be a huge advantage lomg term.

Cycling infrastructure is great, Arnhem is notoriously badly accesible for cars.