I did this trip with JY in March 2014 and the itinerary doesn't seem to have changed much.
The first 5 days are quite busy but things slow a little after that depending if you wish to go on all the 3 optional tours. I did all of them and didn't find it too much! The trip to Halong Bay is the most hectic part and the bay itself does get quite misty at times.
Travelling with JY means that all arrangements are taken care of but you are not forced to conform - you can have your own space. However your fellow passengers tend to have one thing in common in that they want a shared experience of the places visited.
My tips would include that US Dollars are useful but in small denominations - 1's and 5's. You need to take insect repellent and to wear it! Plus take some hand cleanser. Then enjoy the sights, sounds and smells! It is such a vibrant region and the locals were lovely.
Hope this is of some help.
