DarkLogixTexan and ProudPremium
If possible yes
only issue I see there is you say each location, ie MDF and IDF, the link between MDF and IDF should if possible not be a bottleneck, which from the sound of it, it is.
I suspect the bogging you're seeing is the uplinks getting maxed not the switches themselves.
Also if possible stagger the backups, not just use non-peak but lower the number that are occuring at the same time, so that multiple backups aren't competing for bandwidth.