We know that making shields bigger weakens them ("Mudd's Women" already established this), so this might make bubble shields less desirable than skintight ones. On the other hand, it would be easy to argue that stretching the shield over the complex shape of a starship will weaken it.
My guess is that the 2 styles are a result of 2 ways to generate the Shields. Bubble shields come from large generators mounted centrally inside the ship, better protected but when damaged most or all of the shields drop. Skintight shields are generated from smaller emitters distributed throughout the outer hull. That way only small sections of shields can be taken down at a time from enemy fire, unless the take out the power supply.