Here are some suggestions:
Stand still with eyes closed, on a cushion or pillow.
Stand toe to heel without moving, eyes open/eyes closed/on a pillow or cushion
Toe to heel:
Stand on one foot with eyes closed, can also repeat on cushion
Business Card Still & Moving:
You can do this while walking forward/backward or doing any of the balance/toe to heel exercises.
You can have a busy background, such as a checkerboard, in the background
You can identify movements that increase your symptoms. Try to break it down, take one piece of it and repeat it, over time build up your number of repetitions like you do with the 1 min head turns.
Keep up the good work!