I suggest picking arty cover doctrine it has a lot of advantages for new players.
Im not a pro I play casual you can check my replays vs OKW I think i did a good job with arty cover, I killed 2 king tigers with a well timed arty cover and aggresive push, i almost lost to those massive shreck blobs vickers held on he gave up 1 hour 15 mins.
My replay
1) if you manage to save your AEC till your first armor make AEC command vehicle ( it gives a lot of bonus your AT guns will go bonkers .. 30% reload, 30% recieved accuracy is no joke)
2) you can save atleast 400 odd manpower if you spend 150 munition on AT and vickers drop.
3) OKW struggle with supression, so vs OKW 2 Vickers is a must add 3 with drop ability.
4) use of arty cover.. wait of the right time to use it dont use it defensively, be very aggressive when you use it.
Thanks for ypur replay, I already learned a few things from it like the efficient use of the tactical support commander. I also use Hammer more often now, because the Comet can compete with heavy tanks and the gammons force suppressed units to retreat.
But I still think the UKF seem a bit underpowered, due to lack of infantry strength in the early game (IS can only survive with Vivkers support) and hard-to-handle tanks in the lategame. The only real strong unit is the AEC. I started to play USF a few days ago and they seem to be more powerfull. The agressive playstyle makes it easy to gain mapcontrol and stuarts/ATs/etc will sustain it. The tanks are fast, cheap, easy to handle and are able to hunt down any targets. I reached level 11 within the first 15 games (now 10 again ) and USF are so much fun to play, but maybe it's just because the US Army was my favourite in the first CoH!