I agree that the optional endgame stuff really seemed to get more involved starting with VII. For example, encountering the Tonberry King in VIII required defeating 20 tonberries in the Centra Ruins, and the chances of that happening by accident were pretty slim. I will say, however, there is a certain magic to discovering side stuff on your own. I fondly remember my first time on VI just flying around randomly and discovering new sidequests after I thought I had done everything. Or, the first time I was flying around and encountered Death/Doom Gaze and it scared the crap out of me!