You already know that most hotels have the amenities you want or need. How about things like hairdryers or irons?
If you need a hairdryer, an iron, or any other item it would be a good idea to check to see if the hotel has it.
I always check for hairdryers. Many times the hotel website has listed what their room amenities are...but not always. If I can't find it listed, I call the hotel directly. No sense packing bulky items if I don't need to.