I usually choose Special Operations Doctrine or Luftwaffe Ground Forces Doctrine and follow this build order:
4 Volks
Medic HQ Truck at HQ
Raketenwerfer
Infantry gun
Schreck up every Volks squad
Flak HQ
Luchs
Obersoldaten with StG upgrade or Falls
PIV or Command Panther
--snip--
Got to back this up.
You need to press home the numbers advantage vs UKF, you can and have to out cap them. Pressure the fuel/cut off and force them to react to you. This build helps with that.
Be careful with the ISG, don't leave it un-supported otherwise it will be food for commandos.
Also, be mindful to get the luchs quickly. An early luchs can remove most of their infantry without much hassle but you have to be careful and avoid mines.
Going Sturm heavy would enhance your early game advantage in terms of KD, but it'd screw your map control and leave you really vulnerable to Wasp in the early/mid game and then to basically everything in the late game.