When we bought new luggage last year I also bought heavy duty plastic covers for the pullman cases. So it is easy to spot the red bags with the plastic covers, and it sure protects to luggage. Years ago I also bought luggage straps with our names woven right into them, but with the covers don't use them much anymore.
We also take clorox wipes in a plastic bag and clean everything in the stateroom when we arrive. Including the TV remote, telephone, door knobs, vanity surface and any thing else we will be touching. We also take along a bunch of alcohol wipes that the casinos pass out to have with us when we are ashore.
We too do the business card thing and the egg crate. On our most recent cruises I replaced my classic carry on case with a day pack. It works great for all my electronics and cameras, meds, etc. and it really comes in handy for shore excursions, even has netting one each side for water bottles. It also makes a great place to display on the little "pins" I pick up from various countries. Also have a small clip on compass attached to it.