See I have tried every class and my favorite is the hunter, but I think we get the real advantage honestly. I mean sure, on average, the other supers are extremely powerful and tank mode. They have awful balance issues, I agree with everything you said there. But there is a reason the top 20 players are mostly Hunters.
Our skills, while not the easiest or most glamorous, can be amazing. If you understand PVP well, or have good combat knowledge and instincts, the skills like Golden Gun and Throwing Knife are far superior to anything the others have. Golden Gun has significant range and boosts like when you knife people and all. It is also a very easy way to kill people if you know how to aim. If you use it at the right times, which are often because people are predictable, you can dominate with it. Throwing knives are also really good for that, and our grenades are the best of the bunch imho.
That said, there are other annoying issues with the other supers. The Nova Bomb you covered pretty well, but I will elaborate more on it. The blast is massive and stays a long time, and you can't really see through it well, so it is blinding - bad for everyone. That goes for their grenade as well. It has a radius that is far larger than it ought to be and can even get you in the air with no trouble.
The titan smash thing, I can't remember the name, is ridiculously annoying. Most of the big objectives are around tight corners so they come at you quickly with no way to escape it most of the time. Not only that, but they can get you in a ton of different ways, air, distance, or post-mortem. The shocks at the end are frustrating beyond belief, and they have such a big radius.
Golden Gun doesn't have a post-mortem effect, and you can lose everything during it. But it can chain react and it is extremely useful for taking out scattered enemies, and it also lasts far longer.
