I believe I have found THE perfect Universal bag!!
I've always carried a mini backpack to Disney and up until recently at Universal. Now that the kids are a bit older and we usually stay onsite at Universal, I just don't need that kind of room and don't want to deal with the hassle of carrying it. I would still like to have a place for the cell, camera, hand sanitizer, tissues, glasses, credit cards etc. and this little bag holds all of that and more! BUT, the best feature is that it can be worn as a purse over your shoulder which I'll do 98% of the time and then converted in seconds to a waist pack for those rides that won't allow bags.
As far as the room keys go, I have the hotel hole punch it for me and wear it around my neck on a cheap lanyard type string I picked up at a craft store. That way it is easily accessed for the ride attendants. Everyone in my party wears theirs that way.
This looks Perfect! I am getting it today!