If I recall correctly, CE's main charm is that you can edit any program's memory.
Usually not an issue in multiplayer games where the server barely trusts the client, anything you edit on the client remains on the client and/or is double-checked by the server, and does not affect other players.
Considering the kinds of hacks we've seen for BF3 though (teleporting other players, adjusting bullet damage)... the server seems to trust the client a whole bloody lot. Could be similar for BF4. CE could be used for quite a bit of havoc in that case.