Make your life easier.
Luggage and bags: If it doesn't go on your back, don't even think about bringing it. Slick wheeled luggage works great on paved concrete and airport tile, not so great navigating crowded trains and trecherous cobblestone.
Toiletries and Medical Supplies: Your own toiletpaper and everything else to do with that area. But look forward to getting your own painkillers in Prague's pharmacies.
Miscellaneous: ENGLISH SPEAKERS: BRING A CZECH DICTIONARY! Navigating transportation and hotels, etc, is easy without it, but menues and shops and bars - you need a translator!
Miscellaneous: Just a buste, I don t remember after 20 years what man this was....
Photo Equipment: Bring someone that can properly compose a photo or you will lose part of the historical archway from the Urquell Brewery that dates back to the late 1800's. ;>