It was a big, epic adventure and I enjoyed it a lot, although part three couldn't possibly top the end of part 2!
I loved the way the timelines were treated - the DS9ers knew parallel timelines existed and theorized that they may be caused by time travel, but they didn't know for sure. Stuff like Odo not wanting to leave Vic behind because this
Vic might be stuck all alone for eternity in an alternate timeline even if everything was reset from Odo's perspective was touching.
I didn't by that technobabble about following identical trajectories to move through time in your own universe, and the elaborate plot to hide time tampering until the last second didn't make sense/was wishful thinking (it's still an alternate reality in which the bombs exist, whether they're found or not. By default there's one timeline where you set the bombs and one where you didn't).
But none of that got in the way of the fun. It took DS9's lore and put it into an even more epic story. Great!