Gratz,
I have my second full team right at 78 also. Once you have a grp at 80 the next group will be a lot easier if you do the BoA chest and shoulders. I have done only abotu 5 - 6 of the collection quests (unless they are 100% drop rates) and I skipped several areas completely.
One thing to always keep in mind is that you can do all the dungeon quests and also any quests which normally would need a grp.
I threw in a few dungeons for experience which also helped a litle but the BoA gear was the biggest help I believe.
Again gratz