A lot of the cheaters do not know where the wall hacks are located. The auto aim features on some of the cheats simply find them and pull the trigger for them. any small opening in a wall for instance that the average person wouldn't notice, is picked up by the box they are using and aim through the spot for them.
IMO, the game doesn't need much fixing, including Netcode. What is needed is frequent community reminders of what a cheat is and the penalties. Also needed is ways to find cheats including the AI methods that are starting to be used in other games.
At a minimum, Continuous Very High K/D ratios should be flagged, maybe moving them to a High K/D servers. Let them cheat against each other until they correct their actions or are caught and banned.
Another possible thing to add, is possibly set an amount of games for Very High K/D. Say for example, if you have 5 Very High K/D matches in 7 rounds, You are flagged and moved to another room. Also, if the same person has the same K/D and have reports against them, co the above and flag for investigation/Review.
One Last thing. Introduce the option of a death cam with the option to playback the kill from the potential cheats view. if it doesn't look legit, have the option to send the clip to EA