Easiest to accomplish in a Tier II Light German Tank with the 2cm rapid fire gun. The enemies you face in this tier are mostly lights and open top (low armor) tank destroyers.
The Pz. II has the best armor including turret armor, of the German lights.
The Pz. 35 has more horsepower and is quicker at turning, with reduced armor.
There is also a Pz. II D premium tank. Though it has a weaker penetrating gun, less power and armor than the above listed regular tanks (once they become fully upgraded).
Other recommendations:
Tier III, Pz. III E - If you can get a favorable Tier III matchup. Of the non-premium Tier III light tanks, an upgraded Pz III E is only bested by the Russian BT-7 in engine power. The Pz. III E has the option of equipping a slower firing 5cm gun with good damage, if your playstyle suits.
Tier IV Tank Destroyers (Marder 38T/Hetzer/StuG III B - in order of preference)
Marder 38T - Usually gets favorable Tier 3-5 matchups. Possibly due to it being open top, poorly armored. Its 7.5cm gun can one or two shot a lot of Tier 3/4 opposition.
Hetzer - A.K.A. the Derp Gun - The 10.5cm one shots many (not heavies). Pros: Low sloped frame with thick front armor, can hide easily. Cons: Slow to reload and its turret is slow to aim. Virtually no rear armor, you won't turn quick enough to stop a light tank from getting behind.
StuG III B - A quicker Hetzer engine wise, but the gun aims and fires even slower. It's profile is more exposed and front armor won't ping shots away like the Hetzer. I've found it draws more unfavorable Tier 6 matchups.
For Arty lovers, the German Tier V, Grille has a ridiculous long range high splash shot. You can get four kills, if enemies remains frozen on the battlefield.