I'm assuming this is based off the Warhawk/Masakari Assault Mech from Battletech, if so then that amount of weaponry seems fairly reasonable, maybe a bit more than the Masakari has but this is simply based off it.
The Warhawk/Masakari only weighs 85tons in Battletech, this weighs a staggering 120tons, so it's essentially a 'Heavy' Assault Mech, which justifies the extra weaponry even more when you consider Assault Mechs like the Dire Wolf that actually carried this amount of weaponry.
Its a Daishi Dammit, fucking Clanner. Also, its more like a Behemoth in appearance, actually like a Behemoth and Amaris's Folly combined in appearance. max speed is sub urbanmech, turns slow, THE GUNS! also, i named it after the Masakari because i love that things name.