Tried the Gladio Score Attack and managed 500k pretty easily.
Might try for the 1mil a little bit later on, as it seems doable if I'm fighting technically and not just going breakneck through everything, and then go back for the Item/Column completion to get back to 100%. I have Gladio's shirtless outfit now, and it's strong on attack, but SO weak on defense.
Additionally, I wish that the Genji Blade was his ultimate weapon, but I'm far enough in to the game that I might just use it anyway. (Also, because while it's totally strong, I'm not fond of the design for the Apocalypse).