Bipedal tanks are not a bad idea, obviously they have access to more impassable terrain. One of the main concerns when designing them is the structural endurance of the joints. That's the risk...you have to balance out the pros and cons as best possible. For example...The Gecko
Pros are it's maneuverability and its' speed. Armaments are two MK2 .50 calibre machine guns but that's about it...it's not used to engage other armor but rather to disrupt infantry with ruthless speed and cause major disorientation within the ranks. Cons are its' legs...obviously, you put enough rounds into it and you'll bring it down. But that's why they travel in packs.
Same thing should apply with the tanks in Destiny...one single tank is easy to overcome if you can get around it...not so easy when you have to deal with three or four of them at once. The tank looks like it's not for combating infantry so my guess is that it will have a large canon along with at least 2 point defenses. The main idea is that you don't want them alone...you could even have infantry support with it.
Below is my old OP from a tank discussion about two years ago...it is most likely out of date but it's a good stepping stone to base ideas off of...
During the 10 long years we've been at war in the Middle East it has become painfully clear that as sophisticated as our tanks, APCs, and IFVs are they can still be knocked out by the cheapest of explosives. The Defense Industry has been on a constant crunch to create the next best type of armor to ensure that the operators remain safe or even prevent the immobilization of our vehicles. Obviously structural weaknesses and design flaws come with the territory and often attempts to rectify these flaws result in sacrifices that are unacceptable to the performance of the hardware in the field. Back in World War 2 the U.S. was far behind in Tank development while Germany(granted they were developing the things year round) being at the top.
Russia produced the T-34 at record numbers and they had a surprisingly high level of quality to them(obviously not as good as a Tiger) but decent to the point where they were useful in combating German tanks....The U.S. had come into the party late but produced a decent tank for the time but the problem was range and armor....The Stewart being what it was was the least acceptable tank to take on the German Panzers due to its' miniature status....The Sherman was an impressive piece but lacked sufficient frontside armor and the barrel length was inadequate for a one on one confrontation....The Americans adapted by having them travel in packs which did give the allies a real fighting chance against the beats of the German war machine.
The British took the American tank and turned it into a remarkable piece of steel. The 17 pounder allowed for a greater engagement range and quicker firing but on the flip killed the tanks ability to be effective against infantry whereas the M4 Sherman was capable of firing canister rounds to deal with infantry within 200 yards. The M4 had a successful penetration range of 1000 yards against a Panzer IV but when Tigers and Panthers made entry the effectiveness deteriorated. Oh look at me getting off track, back to the Firefly. The Firefly 17 pounder was able to penetrate some 140 mm of armour at 500 m (550 yd) and 131 mm at 1,000 m (1,100 yd) using standard Armour Piercing, Capped, Ballistic Capped (APCBC) ammunition at a 30 degree angle. But enough about history.....moving on to this generation....
The urbanization of warfare. The world's population is rapidly moving to the cities. Cities are tough for big, open manuver-warfare-focused forces to fight in. Think Fallujah, Ramadi, Sadr City, Grozny, Hue. No fun. Fighting in cities can reduce American ground forces advantages in stand off weapons, mobility, precision weapons, communications and ISR gear, according to CSBA. Furthermore, urban eviction and control operations typically require use of sizeable ground forces and involve protracted fights incurring heavy casualties. A pit fill of pipe bombs has sufficient strength to knock the treads of an Abrams or Bradley. Even the cheap but practical rocket propelled grenade is sufficient.
[Edited on 12.01.2012 9:36 PM PST]