Right, I just want to post some technical data.
Side step mechanics, I'm pretty sure actually exist in battletech rules under "experimental rules" or Battletech tactical operations handbook. If I remember correctly, they have a number of different movement types that depend heavily on pilot skill to perform. If you fail a roll, it would also have some serious consequences, which include, but not limited to, damage to the legs, damage to the torso, damage to the engine, falling over, and so forth. However how do you simulate these rule sets and roles? Do you now start skilling your character so that they are better at something? Just like the old battle tech, upgrading gunnery, then upgrading piloting, depending on what you want? Or do you go down MWO's new route where you can actually specialize in something?
As for the hip joints moving like human joints, that a YES AND NO, Depending on the mech actually has a massive impact on the range of movement that mech has involving the hip, the Mad cat for example as a much more limited range of movement due to the fact that a lot of actuators to simulate that stuff is spread trough out the leg, as demostrated here:
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http://www.planet25....riginal_205.jpg "
While it seems that humanoid mechs have a much much wider range of movement involving the hips, an example art work of different mechs, with different leg types, in different positions
http://orig04.devian..._by_eriance.png
You have to remember that while the pilot helps with the balance and other such things, mechs have all sort of different leg designs, and thus all models have a different range of limitations and bonuses, while a humanoid legs would greatly benefit climbing, and rough terrain, a reverse joint mech tends to have a much faster flat terrain bonus.
AND ALL OF THIS, is very difficult to simulate in a game, and keep balance at the same time.