Rose is the only character that did not have the chance to be the Main Character and her own flashbacks. So It was time to do it. Has expected, it could not be something trivial, it was necessary to do something special, like locke healed legs for example.
Through this mindset, her Storyline was construted with a beginning and a end. Since she is not a strong character, it was best this way.
Make sense that she is healed too, like Locke, but what was not necessary was for her husband to try to make the signal. This was only to fill the episode.
Other events, like Jack and Kate is a setup, the hatch too.
Emotions - » Since Rose is not a Strong Character, it was difficult to create better scenes, since the majority for the Audience would not care. All the Scenes featuring the her flashbacks is about Sadness and Hope. Typical Lost Drama.
Progression - » Since this is a setup, nothing essential happened, so this can be considered filler. This is all about doing a closure for a character that had not time to be one of the main Cast.
Ending - » Nothing special or impressive.
Overall - » Good Material, but not enough to be Great. Still, is a good Setup with some good material and closure.