I consider myself a good NH, and I've played quite a bit of both sides, it's obvious that the night hunter is at an tremendously extreme disadvantage. The NH defenses have very long cooldowns, using both spits will essentially leave you vulnerable and pathetic for around 90 seconds, this leaves more than enough time to clear a nest.
However the humans have no real disadvantages when they use up a defensive ability. Out of UV? Throw a flare. NH trying to ground pound flare? Pull out the gun, take a step back, and blow him away while he tries to recover from his completely under powered and slow ground pound.
Night hunter tries to tackle human? HAH! LOL!... LMAO JK. Who gets hit by tackles anyways? It takes a new level of bad to be hit by a NH tackle. Its sad to say that the human is actually faster than the NH on short distance sprints upon taking an extremely common speed potion. This makes it very difficult for a NH to escape a clutch situation, and leaves no room for error, since there is a cast time for tendril locomotion, ground pound, ect. Even with UV immunity.
Speaking of which, why can't the NH use melee attacks? Sure sure you are thinking "But Jayce the NH does have melee attacks dur". Yeah? Really? Tell me how many times you have dealt more than 25 damage against a human in a head to head melee brawl. I mean sure the NH shouldn't be better than the human at everything, but at least let him hold his own! I mean really, a runner zombie deals more damage with his melee attacks than a NH.
TLDR: My suggestion.
Remove both hunter vision, and Zombie sense. OR
Add a 15 minute timer to human players so that they cannot just camp a single area until the NH has been killed, and then move up. OR
Make the NH more responsive (Faster cast times, better projectile speed, Faster movement, and less ability interruptions) OR
My personal favorite. Remove the ability to counter the NH so aggressively. Take away the ability to dodge his tackle, increase NH health so that making a mistake doesn't mean certain death, and make it so that landing yellow spit on the player actually does something useful. I cannot tell you how many times I have done everything right, landed that yellow spit, and remained completely unable to get a kill because there are so many ways to exploit the NH abilities and counter him.
Anyways, we all agree that the NH needs a lot of works/buffs. I'm surprised techland hasn't done anything about it yet.