Every character is going to have some stereotypical attributes, that I am going to use in one way or another.
A bit naive and idealistic, but quite vicious on the inside. Very attractive and charismatic, easily turns others to her side. Pursues her goals with no regard to morals or consequence. Her main goal is to survive- and do it with maximum comfort.
She wears leather armor, since she prefers extremely long range battles with her two sniper rifles. Cybernetic arms and legs give her extreme speed in combat. She is a killer.
And she likes fire.
Especially it's smell in the morning.
Smells like victory.
Even though he likes technology, he has a real body, and the hi-tech armor is mere augmentation to his abilities and skills. He can be classified as a close-quarters fighter, but prefers speed and agility over heavy armor. He uses a spear and a tail (or tentacle?) to hold his opponents at some distance (but really, I am just sick of seeing katanas everywhere). For long range, he uses exploding spheres.
Pretty, cold, straightforward and with diplomatic skills of a sewer drain. Still, if you know her a bit, she will show you how warm and loving she can actually be.
She wears a glamorous armor. Always. Since she is at war. Always.
Now combat, she likes it close and personal. Especially against the odds, especially at winter, and especially if it's heroic. She can shoot a bit, but where is the fun in that? Still, it usually clears the riffraff that is not worthy of the chilly, wintry, personal embrace.
The word "pizdec" is engraved on the sword, which pretty much symbolizes the Russian life in any age and era.
There is a bear with AK-47, of course, but it's guarding the nuclear reactor back home. And the vodka. Probably a bad idea though.
Germany is considered to be clean, orderly and modern, so he wears a mechsuit. Something like an Ironman suit, but with more precision German engineering in it. And more stylish. Unlike earlier times, he mostly fights long ranged battles now, to keep the suit clean.
Has unfoldable wings and thrusters on his back, like any proper mecha should.