A little lengthier, I like the idea that the Typhon Pact isn't "just" the New Soviet MenaceTM (which would be ironic because of Checov). It's not a Legion of Doom-style organization like the Klingon/Gorn/Orion alliance is in Star Trek Online either. It's an alternative organization to the Federation for people who think the Feddies are a "homo-sapiens only" club. If you're a pessimist, it's an alliance existing in much the same was as the (evil) Federation/Klingon one in TUC, more or less to preserve the right of stomping a boot forever on freedom in their territories.
However, the funny thing is that even poisoned Earth can occasionally give healthy plants. The Breen, Tzenkethi, Tholians, and so on are all completely opposite in HOW they're opposed to the Federation. Assuming the Pact just flat-out doesn't fall apart or lead to war, you're going to see free trade and exposure of ideas which will undermine the values which keep everything vile going in these groups. The Breen, for instance, are racially tolerant while the Tzenkethi (actually I've got nothing for positive qualities about them), and the Gorn are an okay bunch when they're not being threatened.
If I may ruin my argument, I'm reminded of Angel One's ending. The alliance is an attempt to halt evolution but it's only going to delay it (if not actually accelerate it). Still, I'm hoping I'll see plenty of uses of the Typhon Pact AS villains in addition to seeing them as a positive force. As much as I love Klingons, they're a horrible bunch of people and if an alliance existed between Genghis Khan, Atilla the Hun, Qin China, and Colonel Green--I'd expect some nastiness.