Taiwan brings back memories for me! I have been to this beautiful island 5 times! Tips for you would be to carry light and enjoy the trip. Never leave anything important on the bus. Since you are with a tour group, there is time constrain on your journey. My advice would be to carry light and with just 1 lens as you do not have the luxury of time to wander around much with a packed iternary that is customary of a tour group.
Reasons as to why I have been to Taiwan for 5 times? First, it was due to National Service and I spent 3 days R&R there. I am hooked by the natural beauty and friendly people that this island has to offer.
During my university days, I went with 2 close friends on a 2 wks free-and-easy tour of Taiwan. We went from Taipei and went clockwise around the coast of Taiwan. It costs us barely $1K each inclusive of the air tickets and the food and the lodging. Of course, we walked a lot but the trip was memorable.
For the 2nd time, I went with my colleague and for the third time, I went with my parents and a close fried
For the 4th time, I went with my wife.
For the 5th time, I went again with my close friend, this time conquering the offshore islands. It was fantastic!
Enjoy your trip!