Ditto with Merridy -- she is wonderful. Another one is Dorothy Whiteman in Elma, a wonderful trainer for general driving, combined driving and breed show.
Be sure to check into the driving forum on Lil Beginnings, and if you frequent Facebook, sign up for CDE4VSE, PNW Recreational Trail Driving Guide, and other driving groups.
If you are within a reasonable distance from Long Beach, we're having a beach drivers' weekend August 23-25, camping at the Peninsula Saddle Club and driving on the beach at low tide. We have a GREAT time!
Getting back to your initial question, the real question is what CAN'T you do with a mini? You can do everything but ride.