Probably easy changes listed in order of importance that will greatly increase the quality of sPvP.
Most Important ATM
Flashbang: Rework the skill so it does something other than blind or CC
Auras: Change back to their previous form and remove the UI icons for clarity (or even just in sPVP)
Radiant Fire: Remove passive skill procs (rework if necessary)
Scourge Shade Skills: Revert that change that allowed shades to apply their effect around the necro as well as the shade.
Shade skills: Alter the visual tells so that it's clear what shade skill the scourge is using.
Full Counter: Daze Duration reduced to its original 0.5s
Forced Engagement: Increase the cast time for this skill + decrease the targets
Blinding Ashes: This skill now causes fire auras to deal more burning damage to melee foes and loses the ability to burn ranged foes.
Juggernaught: Alter the trait so that instead of pulsing stability, stability is applied by using any flamethrower skill except skill #1
Flash Shell+Supply Crate: Now apply blind on cast instead of pulsing.
Elixir S: Now functions like all other invulnerability skills, preventing revives and stomps.
Smokescale Pet: Disable in PvP
Throw Shield: Applies Vulnerability instead of dazing
Signet of Mercy + Battle Standard + Glyph of renewal: Casting is 3 sec and generates a visual effect connecting the two players
Rune of the Trapper: Rework final bonus
Glyph of the Tides: Increase the Cast time
Planar Protection: Rework. Less skill stacking the better.
Scorchrazor: Increase the cast time of this skill
Gale: Now has a visual pre-effect around the target.
Phase Traversal: Require LoS
Not AS Important ATM
Test of Faith: Add a cast time.
Axes of Symmetry: Remove the un-listed stealth component of this skill
Acid Bomb: Now displays area of effect circle
Lock-on: Require an actual trigger requiring skill
Thermal Release Valve: Now deals more burning damage but cannot remove heat unless in forge.
Lich Form: Deathly Claws: Damage is reduced my half
Lich Form: Lich's Gaze: Now deals increased damage and chills
Lich Form: Summon Madness: Drastically increase explosion damage.
Terror: Fear now deals it's damage only at the end and only if the player didn't remove the fear.
Rune of Air: Rework the final bonus.
Ancient Seeds: Vine Surge now applies the ancient seeds if it strikes. That, or something less more active and maybe less frequent
Protective Ward: Reworked into something active.
Beastly Warden: When the ranger has this trait off C/D the pet glows red or something.
Marching Orders: Remove the ICD. All associated traits are appropriately nerfed to compensate.
Brutal Shot: Now activates instantly, doesn't try to make the character face the target, and deals little damage.
Stomp: Is immune to blind.
Method of Madness: Rework
Versed in Stone: Remove the auto-activation aspect.
Primordial Stance: Now functions like arcane precision except crits are not required.
Inspiring Reinforcement: Move the stunbreak from Rite of the Great Dwarf to this skill or switch the Cast times of the two skills. (nerfs may be needed)
I will be modifying this list if/when priorities change or things get fixed. There are a lot of things that need done but require more work. Definitely not falling into the "balance/minor rework" category.