What are the first upgrades I should be getting ? Sights and primary upgrades like foregrip?
Also which class has the anti rpg rocket?
Depends on your play style. You need to consider;
1. Do I engage at long, medium or close range - this will choose your scope. Tip: the best scope is the night vision or the reflex for close range combat. The ranged scopes depend on the gun but its prolly not worth getting the best magnification scope for any gun, other than the sniper rifles.
2. Do I prefer to use ironsights or fire from the hip? iron = foregrip, hip = lazer dot. If you are a hip firer and don't mind engaging at close range the lazer dot is a win button at the moment - its a "see your k/d triple with just a single upgrade" kinda win button. I am not joking.
After that its up to you, but soft point ammo is generally a good move unless you like to use range.
All rocket launchers are available on the Heavy Assault class. The basic one you start with a dumb fire, medium damage rocket. You can then specialise in anti vehicle or anti air (lock on or dumb fire, good damage) or a anti-V anti-A lock on (no dumb fire, medium damage). I recommend specialising - personally I have gone AV.
If you have station cash in the bank I would strongly advise choosing the right gun before you start throwing certs around.
Heres some tips:
1. Usually the "Best" gun is the one with the same stats as the starter gun, but with better fire rate. This applies to medic and engineer to some degree.
2. the engineer has one gun that can attach an underslung grenade launcher to it. This is a great for laughs but costs a lot of certs to spec it out, you only get two grenades before having to resupply and the actual gun is worse than the starter gun. One good thing is that the U/S grenades do not cost infantry points (unlike normal nades, mines, C4 etc).
3. The sniper rifles - there will be one with no stat for fire rate - this is the bolt action one shot one kill sniper rifle. Hit the head and they are dead.
4. If you are TR or NC you should have at least one class you use shotguns with. VS shotguns don't quite cut the cheese.
5. The heavy assault class starter gun is the best one for its class, except for the MCG (TR) or the Jackhammer (NC - Shotgun). The VS Lasher is a pile ****e.