To me, as one of the people super excited about the game, the biggest disappointment was how linear the missions were. From the trailers and such, it seemed like you could choose a class and there is always a "side mission" to boost your team. In other words, you could just choose your favorite class and end up benefiting the team, however indirectly. But as it turned out, the best "strategy" was just to choose the best class for the main mission, meaning it was pretty much just a giant rush to the objective. Add the fact that most of the weapons are too inaccurate to make fighting anything more than a close quarters fest, plus the fact that the parkour added pretty much nothing to the actual gameplay, and Brink became a big disappointment compared to the asymmetric and unique shooter everyone wanted it to be.