Missions can be frustrating. The battles themselves aren't particularly terrible, but the entry requirements suck. You need a party of people who are of sufficient level, make a good job combination, and, most importantly, are on or past that mission fight.
This last requirement is especially problematic in Wings of the Goddess, because you also add the provision that the rest of the party must have been on the same nation quest line as you.
This makes it especially difficult to get pick up groups going. Even if you could get a pickup group going, at, say, WOTG 24: Distorter of Time, there's a high likelihood that different people are on different nation quest paths. So even if you decided right then and there to form up a static, you wouldn't be able to proceed to the next mission (Prelude to a Storm) unless everyone were to backtrack and do the same quest line.
Also, although you can do the fights with less than a full party (I did most of WOTG with 4 people), if you feel you want to call for outside help, and you have friends who are willing, they may not be able because they haven't done the missions.
So can we implement these two changes please?
1) Separate the WOTG nation quest lines and the main missions. They don't really dovetail storywise.
2) Allow anyone who wants to enter a mission battlefield provided the party leader is at least as far along. The helpers could fight, but they just wouldn't get the cutscenes or credit for the win.
Suggestion number 2 is already in use for A Crystalline Prophecy, Shantotto Ascension, and Moogle Kupo d'etat, and for Nyzul Isle (although that's not a storyline thing). So it seems it can be done. Why not stretch it to the other story lines?
I'm fortunate enough to be almost done Wings of the Goddess after pulling together a static party that ran into a lot of trouble with people dropping out and being delayed due to real life things. A lot of folks aren't that lucky. Though my work isn't totally done, since I did the Windurst quest line and want to do the Bastok and Sandoria ones too. Gonna have to do that with the 3 man remnants of my static