I'd add a pair of small scissors for clipping threads. I have a couple of pairs of the kind that are open and you squeeze them to cut. I found the cheapest ones at a LQS for about $3.00 were the ones I love.
The other thing I use is a lot is the Clover Chaco Line marker. It helps me mark things, especially when the friction pens don't work, which seems like most of the time. I bought some of the Pounce iron-off powder to fill up the marker so I know it will come out if I use it on the top of my quilt.