Fully charged shots pierce through multiple salmon. Always remember that because it can be suprisingly good at crowd control.

With the charger, you have to pick your battles much more carefully. You can't really run into a salmon controlled territory and battle your way out, you have to line up shots and know how to escape those area or you will be splated easily. In general it only has a clear advatage over the Steel Head, but the range can help wound distance striking bosses like the Drizzler and Stinger.

The main thing is keep yourself at a distance from crowds, always near ink and be ready to help revive teammates.

All that being said, yeah I hate it as well. Also the bomb rush is near useless besides if you are going one on one with a fly fish as in most cases if any chum are near you they will rush up before a bomb even goes off and splat you.

Using the stingray on the Flyfish kills it almost instantly.

Salmon Run is open again.

From the Salmon run manual:

2.3.6 Goldie Seeking
...
The Gushers emit light when you hit them-the brighter the light, the closer you are to that glorious Goldie.
...

Looks like there is a way to skill your way through this segment.

- At the beginning of each wave is an indicator of tide level at the bottom of the screen. Keep an eye on this so you can get a few spare seconds to get into position and ink as much ground as possible.

- Do ink the ground before AND after each wave. Can be a life saver, especially on high tide.

- Like you said, kill stingers as fast as possible.

- If someone has the charger always try to get into a higher position. It sucks for Salmon Run, but so does that very slow roller too. The charger is good against Steelheads and the Mothership phase. It is always wise to support the charger player by keeping salmonoids away from them so they can target in peace, especially if you have a very short ranged weapon.

- Those cannons that sometimes spawn on low tide are very useful. Enter them in squid mode and refill ink like you normally would.

- Maws CAN climb walls.

- If you have enough golden eggs and it is getting hectic simply run until time ends.

- During Goldie Rush waves the enemies target the Inklings surrounded by fireflies. Stay near the egg basket.

I guess the charger's job is to focus on bosses and play as a support role while being far. 

Not gonna lie, I feel slightly more validated by the fact that so many people curse the Charger in Salmon Run too lol. I definitely see that it has potential, I guess I need to practice with it way more!

Not sure if this was just for my match but one thing I have seen in a few Goldie seeking rounds, sometimes the gusher the Goldie will jump into will be the exact next spot it appears so if you see a goldie jump into a gusher, try opening it again, it might be in there.