So the other day I had an idea for an challenge category which was Platinum%. I think this could be do able although it would require two playthroughs to finish that might be one of the reasons this isn't a category, does anyone know if this has been discussed and does anyone else think this is a good idea as well.

thanks.

it would take a week

That idea might be fun as a challenge runs, however All Collectibles somewhat fulfills that 'completionist' niche that you're good for. We do appreciate new ideas however!