Some of the strategies seen there:
gun turret
wall-hugger
corner-hugger
wall-hopper (like wall-hugger, but will move to other walls if in danger/getting pounded)
corner-hopper
hesitator ( the idea being to use depletion of energy to halt one's movement, thus throwing off opponents' shots)
machine gunner ( overwhelming rate of fire. Overwhelms opponents that are "too smart" defensively.)
dasher ( rush opponent, deliver kill shot at close range )
a number of strategies depending on weapon type
Some of these strategies might not be applicable, depending on the game physics.
It has also been observed that many robots that rule in single combat often die quick, horrible deaths in a melee. Changing strategy for the number of opponents and/or the presence of teammates is a must.
Now how can explain to my wife why I 'need' to waste a few hours?