Thanks.. I try..Let us hope I can keep afloat... =D
Well, first off it takes five hand seals to preform making it dead give-away. Meaning the opponent expects something to happen if he or she sees the forming seals.It is still performed at short/mid range so a thrown kunai could easily reach them by the time it takes to perform the genjutsu. However it is still effective when it comes to its illusionary prowess. The fact that the user is normally at a distance, hinders the opponent from deciphering what jutsu has just been used. That will give you enough time to launch an attack preferably at high speed. It is a genjutsu that can only be deuced when the petals reach the target.(making it quite good in that regard, unless an elemental/physical technique is used which would go straight through the unwavering petals. A very obvious sign.) The huge flaw is the sheer fact that the petal that cover your movements also reveal the fact that it is in fact a genjutsu. Cherry blossom petals like most petals have a distinct scent, if hundreds of petals were circling you. You would surely receive some kind of aroma considering the fact that there are so many. Petals of all kinds have a scent even if it is faint. In order for the petals to remain upright or surround you there should be some form of wind involved if you can't hear it,smell it or feel it then it isn't there. Running your hands,fingers or weapon through the petals will also reveal the illusion. The fact that the wind doesn't move the petals makes it very suspect from the start. That isn't enough information though, hard proof like running your fingers through the petals and the fact that they have no scent, make no sound, pick up no wind whilst travelling towards you and stay upright in front of you makes it very clear that it is a diversion and a genjutsu.
My sentence structure has been pretty dreadful lately.. Sorry about that..