The dome is a stark reminder of the devastation (and randomness of things that are somewhat spared) of the atomic bomb. However, the dome is just a single building which is fenced off and has a plaque that describes the building, so there's not much to do here. Yes, you can stand there and try to understand why this building was partially spared and not destroyed - and try to understand its significance in the world. But understandably, there's no much more to see here.
However, I would suggest that you go at night to see this attraction. The night lights are strategically placed. At night, the dome seems to display a unique aura and there is beauty (in how it is shown at night) behind all the devastation.