The card Gale reduces the cd of the Healing Totem but he sacrifices his escape ability for it. So its low level doesn't worth to use: Reduce the cd just for a little bit and lose my only chanse to survive? Rather not. So the good players use it on high level (if use it at all). It reduces the cooldown for so much, {1|1}s scaling is realy high among the heal cd reduce cards. I suggest to decrease its scaling and make it independent from his escape skill for make the healer Ghrok a little bit more safe for scrifice some heal cd:
-Reduce the scaling of Gale from {1|1}s to {0.8|0.8}s and independently from the Ghost Walk.
Ghrok's Shock Pulse based cards are literally never used without the talent Maelstorm, but used so much by combinated with Maelstorm, because this talent reduces the cd of Shock Pulse so much, so these cards affects much more often. It makes the things so simple: use them with Maelstorm and not use them without Maelstorm. I think the cards should be viable picks with any talents but not too effective picks combinated by any talents.
Maelstorm also makes the self regeneration impossible for the enemies, because the lighting orbs has realy low cd and increased amount of bounches what is realy annoying.
So I suggest to:
-Reduce the cooldown of Shock Pulse from 6s to 5s for make the cards based on this skill better,
-And rework Maelstorm for don't reduce its cd too much and don't annoy anyone with the too many bounches: Maelstorm: Shock Pulse deals 200 more damage.
Ghost Walk is maybe the worst escape ability in the game (tie with Mal'Damba's Slither), because its duration nerf was too hard (2s->1s). I suggest to increase the duration to 1.5s for make it viable, not just against burst damage.
Spirit's Domain let heal you allies by shoot them. This idea has some plus usage with Pip's same talent, because if the ally and the enemy was close he can heal and the damage at the same time with a good shot. Ghrok can not, so he just got a bonus: it heals more than the stuff's damage. I think shooting allies who doesn't wanna dodge from your lightning beam is basicly boring, but this talent also has two handicaps what make it less useful and annoying to use: 1; Allies' body stop your beam, so you can't shot your enemies while they moves in front of you, even if you wanna rather shot the enemies. So your allies hinders you. 2; You can not self regenerate while you are healing with your stuff, because weapon attacks put you back into the combat, not like any other heals. So you won't regenerate even if you hide well. You have to waste your totem to heal yorself. These are the reasons why this talent sucks. These issues can not be solved just by change some numbers, because these come from its core mechanic. Anyways its avatar is still a totem with a shield aura what makes absolutly no sense to this kind of bonus. It makes sense for the original bonus, what has not disadvantages like this new form, and it was very unique: supporter gave tons of shields. Io already has a talent what gives somthing more with the heals: gives damage reduction. It is cool. The bonus shield was cool as well. Putting it back would be a great step after we got back Androxus' and Lex' old weapon too. It needs some more buffs, because it doesn't need the deploy range boost anymore:
Spirit's Domain: Healing full health allies creates shield with up to 1500 last for 8s.
Haunting certainly was nerfed because it buff the card Gale by combinate them. It's still weak by combinate them, but after the Gale will be independent from the Ghost Walk this card would be absolutly trash. I suggest to buff its scaling from {0.6|0.6}s to {1|1}s for make it worth to use.
Lightning Rod: It heals Ghrok when his Shock Pulse bounches. After Maelstorm's insane cd reduction removal and the bonuch bonus removal it will become realy weak. If its scaling would be buffed from {30|30} to {50|50} it would worth to use (with any talents).
Tempest's speed bonus and slow amount (60%) is insanity it makes the game chaotic: allies gain carzy speed buff and enemies recieve too much slow what can not be countered by good positioning. If it was slightly reduced (60%->40%) and the damage was buffed (200->300) than it would be still good and make the speed difference manageable.