purposely avoiding spoilers for those that have not yet seen it.
Although the Astrid story line seemed a little "forced in" I did like the fact that it explored some of Astrid's story since she is always such a background character and w never learn much about her.
But in this we do learn a bit more of her personality (it's easier to identify given the alternate Astrid to compare her to) as well as bits about her family and also the 'end' says a LOT about her character as well when put in context with what happened a couple scenes earlier.