Fighter is strong right out of the gate. Kensei has a very smooth progression through Heroics and i dont put any points in Vanguard until level 15 opting for THF with a great sword or a falchion before then.
Paladin is better played with THF as well early on but doesnst get Holysword until level 14. Fighter gets Kensei Strike With No Thoughts +1 crit multiplier at level 6 which is great with a THF weapon like a Falchion early on.
A Vanguard wants a Bastard Sword or Dwarven Axe for the wonderful Strike Through mechanics which need the THF line so why not use a THW early on?
Tactically as a new player your stuns and trips will fail a lot on a Paladin. Fighter gets four Tactical feats (+2 +4 +6 +8 = 20 DCs) perfect for the newer player.
This is about Vanguard i know but a new player will probably spend more time in Heroics and VG isnt fun early on.