I've finally found my go-to build/load-out.
Primary: ACR w/FMJ
Secondary: Striker w/Grip
E: Semtex
SE: Flash Grenades
Perk 1: Scavenger Pro
Perk 2: Cold-Blooded Pro
Perk 3: Ninja Pro
I've completely fallen in love with the ACR. The accuracy over long distances is fantastic and something I can't live without anymore. Considering I want super-high accuracy, that left me with 3 choices: Famas, ACR or FAL. Basically for me it came down to the fact that I needed a gun that was automatic. There are too many times in close combat situations where the FAL and the FAMAS leave something to be desired, so the ACR let's me put on the pressure and disrupt the aim of the attacker. The iron sights are also boss as hell (second to the SCAR) and allow me to take some other perk than Bling.
Went with FMJ because the ACR is a bit gimped on damage and there are plenty of times when I need to hit fools through cover/walls, so this will let me do that with greater efficiency, and none of the other attachments were really doing it for me (having a NoobTube actually makes me play worse). I'm sure most people would say "Why not a silencer with that Ninja build?"...and the answer is "The ACR is gimped on damage enough as it is... I don't need another modifier fucking that up." I tried using a silencer, but too many times did the enemy make it around that corner, finished me off...I need that gun doing it's maximum damage potential, not it's minimal, considering how weak it is by default.
The Striker is my favorite shotgun by far...and adding a grip just makes it amazing. Shoots very fast, for solid damage, with fairly good accuracy with the grip. I've emptied rooms full of campers with that thing, and with the large clip size, I can hold down a position by myself without reloading for a good bit.
Scavenger Pro is fantastic as I'll never run out of ammo...and I'm not dying often enough to get a fresh stock, so I need to restock on the field. The re-upping of my Semtex nade is also so good.
Cold-Blooded/Ninja Pro are so I never ever ever show up on radar or sound unless I want to (shooting). People are so obsessed with their radars and heartbeat sensors that being invisible to those devices just disrupts everyone's expectations...plus it's nice not to be airgun fodder.
The key to this entire build is to take your damn time. Last night I was playing with a bunch of friends and I was probably going 4:1 in most of the games we played with this build. Biggest thing I've recently changed up is that I'm not trying to sprint everywhere anymore. Moving more deliberately. Retreating into advantageous positioning if I hear people coming instead of meeting them head-on.
Oh...and I last night was my first time using these:
Fantastic. If you're at all wanting to take your game to the next level...by all means buy these things. So much easier to make minute adjustments for those long distance shots.