It took blizzard years to balance their RTS games. Trust me a year in a RTS game is not a long time. RTS is one of the more difficult games to balance.. every unit has to be good and cost effective yet it cant be OP when massed either.. units also must be fun to use for veteran players but still easy to understand for beginners.. add to that Teamgames and you got a shitloads of work cut out for you.
Im very impressed of relic.. their patching the last 4 months have been fairly fast and mostly the correct changes.
We are not there yet but we are a lot closer than at release =)
Comparing Relic with Blizzard is a bit unfair. Blizzard had to balance 3 races, which can be played in 6 match-ups. Relic only had to balance 2 races, which can only be played in 1 matchup. On top of that, SC2 is a much, much more complex game than CoH2 in pretty much every way.