First things first: This unit's role as a 'planetary assault mecha' makes no sense. The role simply isn't viable enough, since taking a planet is just so ridiculously hard with ground forces that it isn't even funny. That's why the NDI maintains a relatively small ground military that is moved in only for small engagements to secure a single objective or as an occupation force (and is always backed up by its fleet).
Same thing largely applies to the Star Army. It just wouldn't be worth the casualties to invade a planet en masse. It'd be much simpler to send in LAMIA strike teams to capture specific objectives and use the force of space superiority to beat the enemy into submission. When you've got ships capable of wiping out every major population center and/or destroying the planet outright, once you establish space superiority, the battle is largely won.
Moving on: Andrium and Zanarium are lightweight armoring materials that can be (relatively) easily breached. Both are patented products of Phoenix Corporation so if you're using it, you're either doing it illegally or you're paying Phoenix Corporation royalties.
Also, at 15 meters wide, 30 meters tall, and only weighing 60 tons -- this thing is a deathtrap. An infantryman with anti-tank weapons would break this thing apart simply by putting a TAC missile or soliton beam blast on the structural weakpoints. It's too big of a target and the dimensions and weight suggest that per square inch, it's actually less armored than a tank of the same size. A 60-ton tank would not only be cheaper, but could mount more weapons, armor, and survive a whole lot longer on the battlefield. Mecha, even on the human scale, are engineering nightmares. This is why big ass anime mecha aren't feasible and why the NDI and Star Army have abandoned them.
NovaCorp Heavy Assault Rifle (NHAR) : the NHAR is the latest in mecha weaponry - the downside being that only the Juggernaut can hold it because of it's size. The NHAR is essentially a giant gauss rifle that can accelerate it's ammunition up to just under light speed. Because of air friction, the original bullet turns to plasma almost immediately and causes moderate shield damage and extreme damage to any unshielded target. Because of the speed the plasma moves at, it is likely that it will punch a hole straight through it's target. The NHAR also uses the auto-loading system of the juggernaut which contains a further 150 clips for the weapon. The juggernaut can hold up to two of these at any one time.
If the bullet turns to plasma, then why not just use a plasma rifle that uses hydrogen or deuterium as a fuel? You're trying to get too fancy. Simplicity is the name of the game.
NovaCorp Industrial Jump Jets (NIJJ) : three massive solid fuel rockets aided by anti gravity that can propel the Juggernaut through the atmosphere in low orbit at speeds of up to mach 6.
This thing weighs 60-tons and yet is using solid-fuel rockets to move at 6 times the speed of sound? Either one of two things is gonna happen: This is a one-time use thing or you've got to be carrying a shitload of solid-fuel in order to sustain this thing (in which case, this thing should easily weigh many more times than it does).
Ultimately, this entire unit just isn't militarily feasible. It's too big of a target, would cost too much, wouldn't survive long enough, and doesn't pack a big enough punch.