Sents should not have Falcon. Its far too effective for what a secondary on a light class should be. The sniping on the other hand is not a problem at all. Its completely fair and its exactly what they are supposed to do. The two best defenses in this game are either having the other team's flag or a good sniper. Chasing is hard shit and a flag defense is easy to remove(I can get a tank and destroy it from one base to another on most of the maps). Therefore you need a sniper.
I've taken a lot of hate in this game by being good with the tank and harassing snipers. I am that Inf who goes over to the other team's base and starts to hunt down the snipers for the game if they are a problem. And guess what, it works and it helps your team tremendously. Even if you don't kill them. Having them know there is always an inf on their ass drops their play. As long as you have a decent runner or two. They'll start to get those flags. I use a tank for it too. I can clear their defense and show snipers how to snipe, with a tank shell
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2nd, even if you're route is 300. How are you getting to 300? Since the changes, I've been seeing so many bad PTHs. Largely because the Nitron boost was covering up poor routes. So they are going in there with 200hp to get a flag. Yeah they are going 300. Yea, my Inf can one shot their ass now with a pistol.
Switch up your routes too. Try to take a more hidden route and don't go to high. Bee line it. The risks are that it is easier for chasers then, but harder for snipers.