Looking ahead to 7.0, I think Transcendence could be on the chopping block. In PvE, it’s used a lot to reset fights. I don’t think the devs would consider that intended. It has also been used to nullify boss mechanics, such as when BrM’s used it on Imperator. That doesn’t happen often, but it seems it’s always a BrM that finds a way to overcome mechanics the other tanks can’t and Transcendence is one offender. Plus, with Roll, level 15 talents and Flying Serpent Kick, Monks have plenty enough mobility without Transcendence. From a PvP perspective, Transcendence is primarily a defensive spell used to get out of trouble and out of the fray, not into the fray. I think if WW Monks were buffed in PvP in one areas they sorely need; self-healing, defensive's, counter-snare, or countering opponents mobility, that coupled with Transcendence, a good WW Monk could be virtually unkillable in the hands of a good player. I’m sure there are probably some people that love Transcendence and use it in interesting ways, but I think you’re in the minority… we’ll see based on responses.
If Transcendence were removed and replaced with something more offensively minded, I think Clash could be a more than suitable replacement. A lot of people didn’t understand Clash because they thought it was a Charge. It’s not. Clash is a Death Grip + Stun. Monk’s having Clash, could be the PvP buff we need, because WW Monks, are without a ranged snare, nor a teleport to melee range like Shadowstep or Death Grip, and have to spend a GCDs on Disable, which deals no damage and requires melee range. I also think there is great potential to glyph Clash, such as making it so you don’t move, which makes it behave more like Death Grip, or applying Disable instead of stunning, because may be you want to time a Stun and not have it affected by DR. These glyphs exist assuming that the 5 mandatory glyphs needed for PvP, are made not so mandatory anymore. For PvE, having another class that can Death Grip could be useful and maybe bring something to the table in terms of raid utility.
So, if not Clash to return, I think a Hunter-like Camouflage slash D&D’esque Defect Arrows could work. Monks could be immune to projectile based slows. For example, immune to Hunter’s Concussive Shot, but not frost Trap, immune to Mage Frost Bolt slow, but not Frost Armor. Although, I kind of think this kind of ability may be a good replacement for the Ring of Peace talent.