So according to what you're saying, Brits should be god-like in early game and getting "worse" in late, so here we're nerfing brits early game so it's even while keeping late game the same, so brits now are utterly trash faction to play, and still will be trash to play against it, brits are really badly designed, kept some of the worst mechanics from CoH1.
I am not defending the design I am simply bringing it up.
One has to keep in mind that if unit A has better base that the unit B and unit B has better vet bonuses at vet 3 the 2 unit could be become equal.
(For instance although number might no be up to date:
IS base target size 0.8 > Riflemen base target size 0.97
IS received accuracy vet bonus 0.78 < Riflemen accuracy vet bonus 0.77*0.85
IS target size at vet 3 0.62 slightly better than Riflemen target size at vet 3 0.64)
(or the famous myth about commandos and the vet bonuses)
Points here are:
UKF used to had inferior vet bonuses
looking just at vet bonuses that not give the full picture.
I do agree with you that UKF need a better design with more depth.
Imo that can happen if there design with offensive/defensive option with Hammer/anvil becoming available for all tiers.