For a transformation to really register, it should stand out from the character's base form. That's what made the original SSJ payoff so memorable to the fans; at the end of a climatic story arc, our MC basically ascended to the next level and it was totally different than he was. You can still see the core but it's a different feel.
SSJ3 doesn't register like that because it's just SSJ with longer hair, the lone distinguishing feature is the pronounced neanderthal like eyebrow ridges, which is a nice touch. The OD hair just sets it up for parodies, like the one where Nappa gets SSJ3 and his mustache is like 4 feet long.