I suppose I should restructure my opinion that having LD fixed should not be a necessity.
Most if not all of the things LD gave us in melee are fairly arbitrary bonuses given to characters who arbitrarily were able to exploit them. Take samus and the missile, or the low level lasers for example. The advantages gained by these characters in particular aren't universally applicable to every character who should theoretically be able to use them. I haven't seen link throw a boomarang at ground level (it may have happened without my knowledge, I admit). I haven't seen luigi throw a fireball from his "feet" (again, maybe I missed it).
in addition, I think the major reason why this concept is so attractive to so many is because it existed in our favorite game. One could make the argument that any random (but useful) tactic that doesn't exist in reality would receive similar support if it had the same benefit of being in melee. For example, let's assume that a few characters were able to cancel the conclusion of their Fairs by double jumping during the startup time. DK, ganon, the links, and a few other characters would love it. It would increase the depth seen in our game. But since no precedent exists, we don't care. Given more time, I could invent more useful but seemingly random advantages that would play well and increase the skill curve, but to what ends?
Don't get me wrong - I love melee to death, and I love project m already. I'm only here to facilitate discussion on the belief that just because something existed and was functional in melee, it should not be given an automatic inclusion. It is this train of thought that made me think Super Wavedashing should have been left out as well; it can be useful, but it's completely arbitrary, nonsensical, and if it had never existed by what I assume is a mistake (most benefits accrued by LD I admit probably were not mistakes) , nobody would propose such a silly mechanic. LD is significantly less ridiculous, but I felt like showcasing the extreme end of the spectrum to illustrate my point.