When I last played no, it did not. Collector's editions would get unique avatars (essentially the exact same concept as special faceplates) or certain cosmetic "skins" for a unit or two, but nothing affected the stats of the units, or the ability to produce units.
The biggest problem, from my perspective, with SC2 is that the truly competitive scene is essentially impossible to break into. The Koreans, and to a lesser extent Europeans have the infrastructure in place to support people playing the game 10+ hours per day. The mechanics and instincts that these players develop are impressive, but discouraging. I spent a lot of time laddering when the game was new and got decently high (top 10 in my master's league) but when I compared myself to people in the Grand Master league, they wouldn't even break a sweat beating me. The game is very "solved" and there is significantly less tactical depth in SC2 and lot more super fast paced micro you have to learn.
The game was fun for a while, but simply lacks the tactical depth that CoH2 provides. The games are more repetitive and maps have (at least at my level) less of an impact on build orders/timings/strategies. Just prepare yourself for a steep learning curve, and no chance to become a well-known/respected member of the community if you choose to play SC2.
