Emanuel there is nothing to be done. 50% of servers being filled with cheaters is just completely illogical. If that was true there'd be no BF4 players because on the very rare occasion that a cheater actually does enter a server the server completely empties out in a matter of minutes since it's no fun to play. Most suspected instances of cheating is either skill gap between players (with your K\D of 0.49 this is a likely scenario), lag creating an illusion of something that is completely different on the other player's screen exacerbated by client side hit detection, or a combination of the two. Make sure that you are playing on servers inside of your local region to minimize the lag contribution..
Regarding which servers to play on I recommend playing on actively admined clan servers as they can kick suspected cheaters and glitchers right away. Any cheater will most likely go to an official DICE server due to it not being actively admined.
Regarding a refund for the game that you purchased years ago and all other ancillary content, that will not happen. You've played over 75 hours on PC so you are outside both the time played and time after purchase restrictions for the Great Game guarantee.
One thing that I didn't mention is that you can rent your own server from a number of server providers and kick any suspected cheaters yourself.