How would you balance getting up on a hill and having LoS over the opponent's base...off-map arty, scouting his tech...
The terrain would play a vital role , one of the great things about coh was the terrain deformation, it wasnt all just flat, the rises and falls in the landscape are the perfect oppertunity with to implent the balancing of the true sight mechanic in a more realistic way, if you want somewere on a map to be hard to see put obstaces and objects around it, or put it on a hill, under a cliff , in a crevas, really it just means you must keep this in mind when you design a competitive map.
It seems as if certian people are only willing to discuss positive aspects of the game, which is not a good reviewing technique.
And for the record i have played all coh games, im currently playing again on a new acc and have reached around lev 12 with most armies, so i know the basics.