That is a beautiful tank! I haven't kept either the pearl gourami (I have kept a blue gourami) or the ram, but from what I've read I'd have to say the gourami. Here's why, most of the fish you have chosen are small schooling fish, and the bolivian ram isn't that much bigger than them. What you'd want is a fish that will make the tank pop, like a larger, feature fish that stands out from the small schooling fish. The Pearl Gourami would do that, while the ram will kind of blend in with the others, and from the videos I've seen of them, they tend to stay near the bottom and don't make an amazing feature fish that wil show off and cruise around the tank. I owned a blue gourami for a few years and she was the star of the tank, always showing off her colors and staying in the open water were everyone could see her.