Hmmm... All of the units mentioned are ones that I don't use!!
I try to keep my forces mobile though after many many failed experiments with AECS, UCs and snipers I've reverted to using the Bofors and almost always have to pick Anvil.
I've built hundreds of UCs and lots of AECs, tried everything with them but I just suck. Found some interesting uses for them, for instance a sacrifice on both flanks with coordinated artillery when I push the centre. The idea being anything they discover is going to get some well earned 25pdrs to help them out. Oddly they seem to stand up to the later Kraut tanks close in purely because they can avoid the slow turret traverse. Early game though even Volks seem to kill them without Shrecks.
I tend to use Tactical Support Regiment, so no Crocs for me. No idea how to use snipers, they always get rushed and killed. I even put a thread on here asking for replays from someone who knows how to use them.
I find that I never actually push, rather than capping weakly or non defended areas, until I have three tanks. Bitter experience suggests that two simply isn't enough.
Even when I decap and harass OKW's fuel he still seems to out tank me both in numbers and in timing. Haven't had any luck with Piats, if the opposition doesn't leave their tanks stationary then they just seem to miss constantly. Did see a thread from Mr.Smith suggesting some interesting uses for them which I will try but when I come to push I'll usually spend all my munitions on Brens to keep those naughty Shrecks at bay. Especially on the engineering squads.
I'm trying to get a Churchill as my first tank now as it is vital for the first one to survive ( an extra 75 fuel is a looooooong wait though). So many outnumbered Cromwells have gone down.. Don't think I'm overly aggressive with my first one, quite the opposite. One chap did tell me a Centaur can solo a PIV so might try that too. I hate those things, don't fare badly when they go for supertanks but several PIVs is a problem.
I'll usually try to crater one of the VPs I don't own earlyish with my base arty to give my infantry a foothold in the later game ( the dictionary definition of optimism!).
But yeah, I'm rubbish so unit preservation is an issue. I just find that even late game and at popcap when I push, OKW seems stronger. Early game is whack a mole and midgame a struggle against early armour.