TBH as a "medium" player (about rank 200) I have the least problems winning with UKF.
You build a mortar near or in your base that deals constand bleed and is as good as invincible.
The tanks are also great. A Firefly kills all Ostheer mediums in 1 shot if both Tulips hit which is not that hard. Also the Vickers is IMO the best MG in the game en par with the MG42.
I know, I know against very aggressive play, UKF has big problems, but in the non-pro range of ranks you won't see that aggression.
And people ask why British are doing sim city?
It's the only viable tactic to destroy both tanks and infantry.
This is somehow right, for the bleed against OKW blobs you need at least one mortar, but I don't think that the USF lacks AT tanks as the Firefly is imo the best standard tank hunter in the game (without its pathing issues). The Cromwell is an extremely good medium (don't know how it will change without the crush).
Most people forget about the British AT gun which is almost the same as a PaK40 and has a great range.