I usually do the second as the 'stump' of this plant is very good at branching and producing many more shoots. I also float sections of stems because they also produce branches. To explain: if you trim the plants down and then trim all the tops to a similar length, the part that is left with a cut on both ends is capable of growing stems when left floating in an aquarium.
i use complicated method here.in the back i cut the top and leave the botom to grow, in the front - i cut the upper stems and replanting them instead of the bottom ugly ones - this way i get a nice bunch of wallichi. my bigger prob with the wallichi is that the SAE are eating it