You simply spam research stations and unlock everything in about seven minutes of game time. This is a great concept, however in application it's completely flawed. The developers sell this as a method of empowering you to make strategic decisions about which units to unlock.
You have to unlock even some of the basic units through research points. The units you can build initially are limited. Instead you now have maps that barely equate to the medium sized maps of the old game, and a lot less units. What made the first game so good was the epic scale - the massive maps, and stupid number of units. Supreme Commander 2 isn't actually a bad game at all. Is this due to a Defence of the Ancients/Warcraft III influence perhaps? You focus more on particular units, and your commander has become more of a hero unit than in the first game, with many more upgrade options.
The maps are smaller, with more choke points, much like StarCraft. The focus has shifted from technology trees to basic research points. It's been simplified, reduced, watered down. Supreme Commander 2 is not what it should have been. But I loved the competition because they played in different ways. I love Blizzard RTS games, and the way they play. You can see, when playing C&C 4 and Supreme Commander 2, that the Blizzard style of RTS has filtered through. Sure, it's a conspiracy theory, but one I think that has merit. Neither sequel plays much like it's predecessor. And I'm sad to report, both companies appear to have panicked, and reworked their titles. EA knows it, and Gas Powered Games knows it. The only problem was, as the market shares show, none of them quite got there. Rather than playing to their strengths, most of the major electronics companies refocused to be more like the competition. All the consumer saw were rushed imitations of the champion. They took they key concepts of the iPod, and attempted to create their own device. However, what happened next is the key to my analogy. Almost overnight, it became the device of choice for the masses. Design and fashion balanced almost perfectly.
But it did what people wanted, and even more importantly, it had soul. When the iPod came out, it wasn't the first, or necessarily the most technically advanced mp3 player. I'm starting to think StarCraft II is the iPod of real time strategy games.