Seriously, I didn't. When I first did the Costa la Sol part, I was concerned that it was pointless, but when they all gathered at the end to tell you why they did, it made a lot more sense to me and I wouldn't consider it filler.
My definition of filler is anything that doesn't have some explained reason in the storyline, it's just there and has no impact on anything at all.
And I expect to be an unknown to a new land an expansion would bring.

You can't just expect your feats and achievements to carry the same weight elsewhere.
For example, if we got Ala Mhigo, I might expect some people to know me, but as part of the Garlean Empire, other than the events that happened at the Castrums, I can expect that the Empire will keep my name hush-hush.