It would also be great to learn how Captain Braxton and his time ships fit into all of this, as they were from the 29th Century--well into the past be now! Come to think if it, it would have been absolutely brilliant to tie that into the Burn somehow. (Though anything would have been brilliant compared to the crushing letdown of the Burn's real cause.)
If memory serves, the 32nd Century is also when the backup Doctor from "Living Witness" is due to show up in Federation Space. Having him be a part of rebuilding the Federation would also be brilliant. But I guess they'd have to secure Robert Picardo, and then come up with an explanation for why he appears older despite being a hologram.