/sigh. Here we go.
Windwalker: my favorite spec back in MoP. I loved it when my co-tank wanted to solo tank and I got to go dps. Anyways, WW has A LOT of issues:
Mandatory glyphs. For PVP you need Glyph of Touch of Karma, and Touch of Death, and your 3rd is a pick between Parslysis, Freedom Roll, or Fists of Fury (the range one) depending on your avenue/partners.
Damage and healing (and damage reduction due to PVP set bonus) being tied into TeB. This makes ChiEx mandatory for arenas, which isn't fun. Personally I like HS a lot more. I would prefer an actual dos cd instead of generating our burst, but I can live without that.
Squishy as all hell. WW used to have Sparring, a passive that prices on attacks against you that gave you parry. It could be glyphs to work against spells too. Fort Brew is ass-tier as far as defensives go, and ToK is fine for pve, can be fucked over in pvp. WW needs survivsbility that can't be negated by another classes defensive CDs, or tied into TeB (as mentioned earlier due to PVP set bonus).
Fists of Fury. A very heated and controversial topic for WWs everywhere. It's channeled. Why does a MELEE spec have a CHANNELED ability as its big finisher? I'd like to see it either A: turned into an instant that puts a dot on the target for the FoF damage. Or B: less damage in FoF, more in RSK, BoK, HS, ChiEx.
Chi Torpedo. Get rid of it. Get it out of my sight. This is the worst talent by far for WWs who want to PVP. You have to sacrifice your mobility to do dps to the target(s). Why? Why should one of the most mobile specs in the game be made less so with a talent required for optimal damage?
SeF. Get rid of it too. Nobody likes this ability. It causes all sorts of headaches for balancing. WW will never have good single target dos because of this ability. Give us an AOE chi spender besides ChiEx or make ChiEx's AOE stronger to compensate.
Those are the ones that come to mind immediately. Now for some slightly morepositive thoughts! I would love to have an Uppercut ability. Maybe a minor glyph to make RSK an uppercut rather than a bicycle kick.
I would like for Tiger Power to go the way of the DoDo and disappear. Maybe get rid of Tiger Palm entirely for WW, but keep it as is for MW/BrM since they have some sort of interaction with it.
Speaking of MW, why does healing specs RSK hit for more than my dps spec? That's not how this should work, Blizzard.
I'd like more brew-themed abilities for Brewmaster, if nothing else, only so it sounds like my monk is an alcoholic.
That's about all from my mind for now. I'll edit my post if I come up with anything else.