Alright, Ive been playing with some friends recently and the players in my lobby all seem to be new players. Not sure why, but they all go straight for the Guardian or the Marshall. I love these 2 weapons, I think that their amazing, but I don't beileve that they are new-player friendly. I've been playing the game since Beta and in my experience, the best weapon for newer players, is the Spectre.

Spectre
Low recoil
Run and Gun
Friendly
Still teaches pretty good crosshair placement
Fun to use for new players as they get more used to and engaged with the game itself

Guardian
Amazing
Crisp 1 tap potential
Requires good crosshair placement and decent flicking skills to feel satisfying
Have to stand still to properly use
I don't think its that fun to use when you can't get a shot in and getting spammed by other players who are using fully automatic weapons is no fun.

Marshalis nice and cheap, but same problem with the guardian.
Lets be real, unless you are used to playing snipers from other games, Sniping is not a fun thing to do, running around and spraying people down is way more fun

Please, if you can't use the phantom or the vandal, I highly recommend starting with the Spectre.

Edit: No, I shouldn't tell other players how to play the game, Yes, they can just learn it them selves, yes guardian and marshal are great guns to learn. THIS IS ONLY A RECOMMENDATION. And having fun in a game is the first step to playing more.