Flares are better for the jet then the ECM, guided missiles are easy to dodge anyways
I mix a lot, but my favorite is probably PKP Pecheng with Kobra (RDS), Fire grip and Laser sight. Carrying C4 most of the time and claymores if Squad rush or TDM
Tank I usually do with reactive armor, thermal optics and Canister, switch to guided if helicopters in the air and I have a third seat with me
If I got a scout helicopter I use the laser painter, ECM jammer and Guided missile for those instant kills in the air and the attack helicopter is equipped with laser painter, ECM jammer and heat seekers since I usually have a gunner friend with me who use guide missile, will probably change both of them when the patch hits and guided can't hit air anymore
With the Back to Karkand maps (bar Wake Island), I use the F2000 with holo, foregrip and heavy barrel. Metro and Seine is Support with M429 with holo, foregrip and extended mag (waiting to unlock the M60E4 and use the same load out). When it comes to an outside map in Rush with a chopper, I just get any kit because I just jump in the chopper and go to the top of the map and sit above A+B and let people 'HALO jump' down to the MCOMs.