In the trailer I thought Lunagoron was Hisuian Magnamalo,but yeah, in the better light of the render it's more of a Silver Zinogre.
Weapon balance is a funny thing in Monster Hunter. I can see an argument that having power distributed unequally, and with a significant gap between overpowered and underpowered, is in a way good for the game, actually. More personally I don't much care that Gunlance is bottom of the pole with well-known scaling issues, because its move set is fun and longer fights means I get to have fun for longer. I get annoyed that the promoted playstyle for the plain old Lance is anathema to the essence of the weapon, but since Lance is mainly a solo weapon anyway and I don't care much for chasing speed run records, I'm free to say "Fuck the meta" and still go wild building pokey elemental gear sets to my heart's content.
Even for multiplayer hunts, fights are often either so easy they go by fast no matter what weapon you yourself bring or they're on the tougher side and the survivability of some of the traditionally less heavy-hitting weapons becomes a relevant benefit. On that last point, I might be more peeved about the distribution of counters and guards than damage balance, come to think of it.