In hopes to bring awareness and maybe see some bug fixes before 8.1 I am going to tell you the bugs Windwalker Monk suffers from that i am aware of that need to be fixed as some have been in the game since beta (around 7-8 months) and alter the gameplay of the spec some for the better others for the worse

During Storm, Earth and Fire the spirits marks count as 2 Marks of the Crane rather than 1 and are seperate marks. This means when you exit SEF when your Spirits marks fade (they’re seperate so refreshing doesn’t stop this) you lose 2 marks of the crane rather than 1. This puts you into a situation where you are fighting 5 targets, you enter SEF you have a 5 stack of SCK and then SEF ends and your spirits marks fade and you go from 5 -> 3 -> 1 -> -1.
Video Example and Explanation: https://www.twitch.tv/videos/315180925
SEF Cancel aka WDP Bug this is a dps increasing bug where you cast an ability as Storm, Earth and Fire is ending and you lose the buff which splits your damage but you have 1 global where you can input a command to your spirits and cause them to cast a spirit at 300% damage instead of 135%. It is most commonly used with WDP but can be used with any ability. This has to do with the animation of SEF when it ends the spirits return to you and during that time you can input a command. Earlier this year Blizzard implemented a “fix” for this bug where you can no longer cancel Storm, Earth and Fire because people were reproducing this bug with a macro that no longer works but you can still perform this bug manually.
This is a new bug that has been introduced in recent builds of 8.1. What happens is if you tag multiple targets with mark of the crane and your mark of the crane expires from one target you don’t lose stacks on Spinning Crane Kick this makes it possible to maintain 5 stacks on a single target quite easily.

If i missed any important bugs feel free to add them below but these are the important ones that i would like to see fixed for 8.1 patch day. Especially with the new Azerite Trait, “Dance of Chi-Ji” Spinning Crane Kick damage is going to matter much more.

[Windwalker] List of Bugs going into 8.1