Mouse pads are important. You want something that isn't too rough and isn't too smooth, and which is big enough for your mouse movements, but not so big that it takes up too much desk.
Also, I want a gel pad for my wrist to rest on, so I don't get tendonitis.
For many, many years, I've been using the Fellowes "Gel wrist rest and mouse pad". They must be more than ten years old now, and they still work great.
So I just bought four more on Ebay, about £12 each.