Vy works well in the cct. Not least because it is normally pretty close to best range glide speed so if the donk fails, student just stuffs the nose down to maintain (re-achieve) the same speed.
Personally (a grass strip operator), Vx until about 100ft agl or above significant obstacles, then Vy until about 1000ft agl, then something that both gets me somewhere, lets me have a continuous look over the nose and keeps the engine sweet.