As an adept pvper, I would like to suggest a few changes to some talents as the current situation favours a "one against everything" build that can counter anything else. With just 8 points in prophet tree (to upgrade Serenity) and a shield, you can negate almost all type of damages. I will also include a few more minor suggestions to other classes.
The first point is that upgraded Serenity is really cheap to use and even in PvE, it's not practical to have it at early levels. With 5 seconds cooldown, it can negates most if not all damage over time (DoT) spells such as Boiling Blood, Envenom, Sear, etc. and those spells tend to have much longer cd. Direct damage spells such as Bane, Tornado, Ignite also have a chance to be greatly reduced by shield's block chance as it is a go-to equipment for any proph hybrid classes.
The change would be either having Soothsaying be a tier 6-8 talent and/or separate the skill into 2 separate talents: 1 point to remove an extra negative effect, and another 2 points to reduce cd by 15/30s. Having the damage reduction is not practical in PvE either as tank tend to pull a lot of mobs, and early dungeons don't have DoTs to purge. This change will prevent any other classes to spend a very minor amount of talent points to get arguably one of the strongest pvp spell in the game.
The next change would be to nerf Righteous Indignation to just grant removing all debuffs on use and not granting immunity, or at least reduce the duration of immunity to 3 seconds. It is a really strong spell in PvP and has the same imbalance problem like Soothsaying, as all DoTs are ineffective, and it reflects damage from nukes as well as being blocked by shield. On a PvE standpoint, 3 seconds of immunity is enough for an average tank to remove aggro from the healer.
Third change would be to restrict some spells to certain type of weapon. Even though this game encourages hybrid builds, some spells are shown to be very ineffective in some certain builds (because of different armour type), yet some can be easily abused. My proposal would be to require Boiling Blood and Ignite to only be able to be cast with staff (or 2h weapons) and essence equipped, this thus remove the imbalance caused by the use of shield.
For minor suggestions, I would like to have Intense Focus (mage talent) and Wild Instincts (ranger talent) to use the total amount of Focus stat. Boiling Blood cd increased to 15s instead of 10s. Slight of Hand (assassin talent) from 1/2% to 2/4%. Watch Your Step's (assassin talent) slow from 5/10/15% to 10/15/20%. These changes won't affect PvE and promote a wider use of talents.
Thank you for reading.