I found a variety of clevises (different sizes) always came in handy, especially when trying to hook onto tow points on different vehicles. Some trucks have closed tow hooks that you can't hook a strap loop into. Hence the necessity for a clevis.
A shovel was also an invaluable tool, and should never be omitted, especially when going out in the snow. Many times I got stuck in a snow-drift, only to spend fifteen minutes with a shovel and drive out under my own power.
And keep in mind, these are all just basic necessities for the 'just in case' scenario of self-recovery. If you're planning on off-roading much more often there is so much more kit that is necessary, including but not limited to Hi-Lift Jacks, Ground Anchors, Chain Saws, Radios, other vehicles in a group (this is absolutely important).