I've got my kill feed set to everyone so I can see when a tank scrub (saw a level 80 something with 150 service tank stars yesterday) is wreaking and needs to be taken out.
My KD is 1.68 and going up fast as I'm averaging around 2 KD now.
stats here
I'm on XB1 ( I played BF2 and BF3 on PC as well as XBox360 but BF4 wouldn't work on my PC I just got a crash message every time I tried to play it even though the specs were well above the recommended and had to get a refund so from then on it's been console only)
The only issue I've had issues with aim assist is when I'm aiming at one guy in distance and another runs across in front of him and it snaps onto them instead, I don't think I've ever had aim assist drag gun across the screen away from a target, They've toned it down so it barely follows the target now, Have you any videos of it happening or can you record it when it does.
The 'trick' is to get the enemy close to the centre of the screen BEFORE you aim down sight and then even if you don't get on the enemy right away it's close enough that it sticks to the enemy and you can shoot them quick, From what I've seen nearly everyone else when they see an enemy zooms in FIRST even if they are no where near the centre of the screen and so don't get the benefit of aim assist right away and so have to drag the cursor across to the enemy from quite far away so the guy who centres the enemy before aiming down sight has the enemy on target early and wins almost every time, I forgot about this to begin with and had a KD of 1.2ish since remembering like I said I'm around 2 KD now.
If you want to level up scout by the way but don't like bolt action rifles ( I saw you say you were level 10 on all classes apart from scout) then you can use the M1903 Experimental it's basically a medic gun with less damage but it has next to no recoil at all so you can just spam the trigger fast as the added bonus of scout is you can put down flares on flag etc and any enemys close appear on mini map so you know exactly where they are and so most times you will have the drop on them (unless they are just camping stairs etc when it's 50/50.