Even 80 x 50 cages can't please every hamster.I completely understand how it can seem like one size of cage is wonderful and is huge,but really even that size can be a pain due to the width more than anything.
I know my Syrian isn't happy even in an 80 x 50 bin,and I also know that such a size isn't perfect and if anything it just barely allows for enrichment if you set it up just right.An 8.5 inch Comfort Wheel already takes up 1/6th of the cage,then with two hideouts sized for medium to large Syrians half the cage is already filled and these aren't even houses with rooms or anything
I don't think it would hurt to have an extra 20 cm or more of length,but it wouldn't change things drastically either.