I agree that the fillfactor should be carefully reviewed, but not that it's a "small thing". It could have a big impact on performance if/when you rebuild the table.

Unless you do significant increases to the row length after it is inserted, you need to increase the fillfactor considerably. [Even if that is true, I would instead consider "pre-padding" the row rather than using such a low fill factor.]

For a table this large, I usually aim for ~98%, since you typically have to allow for varchar columns to be lengthened on occasion.