Only 3 things I use my shield for.
1: SE3 the dredge cart, shield + WoR + SotA rotate the 3 for an easy melee of the cart.
2: Fire Shaman Fractal, more walls and healing is always nice there.
3: WvW just to push people around, fun to charge ahead of your team right into the opposing zerg and pop it catching anyone without stability and pushing them out of their stack. Kamakazee zerg breaking is so much fun. Sanctuary works well too but longer cast time.
Those are really the only 3 times I pull out the shield.