Since they already implemented the stupidity that was vehicle regeneration, I'm thinking they'll do some more stupid things like ammo that regenerates or environments that reconstruct themselves after being destroyed.
If anything I'm only looking forward to it to see how much more they could possibly ruin the series. Oh and their wonderful DLC schemes are always more exciting than the last.
As for the unlock system, there's obviously room to go dumber. Let's not stop at vehicle unlocks, let's just unlock an entire vehicle starting with the tires. Be it a Jeep or a Jet, you start off with the tire and you have to keep capturing points using the tire until you acquire more parts of the vehicles.
As for maps, they'll top BF3 where instead of shipping with two good maps, they'll just ship with no good maps. That or the franchise will just become solely an infantry combat focused shooter, because for some reason they keep catering to people who like playing nothing but garbage infantry-centric maps like Operation Metro despite the fact that the market is full of infantry-centric shooters. The franchise-ruining-train doesn't stop for Digital Illusions.