Ranged is the worst in my opinion because because spend thousands of resources on ammo and personally, I have more important things to do than gather. Along with that it is quite a struggle to make sure you have the right bullet/arrow for the job in the heat of combat and worms are a pain. I would like to mention that the classes are well balanced and I am only listing the cons of the class that in my opinion is the worst.
Ranged is absolutely not weak. Ichor ammo is basically a good jack of all trades that works for absolutely everything so if you don't know what ammo to use just use that, plus ranged shreds bosses faster than every other class.