I didn't care if it followed the Superman:TAS continuity or not (if it did, I wouldn't be surprised), but I thought it took the whole Doomsday story arc and actually made it comprehensible and good in the context of a feature film (whereas the comic was just plain adolescent and cynical; typical for post-1980s mainstream superhero comics)
Superman: Doomsday WAS adolescent and cynical.
Toyman in some queer Spider isnt adolescent? Kevin Smith's cameo that goes over people's heads not in on the joke isnt cynical? That Luthor's shock value murder of Mercy was logical plottingl? Oh no, Doomsday was wank for Timm fanboy nerds, but a competent Superman story that could have done much more with "Reign"? Absoltuely not.
And "Reign" wasnt a mess at all, it had excellent twists, and Lois's experiances with all of them had some graciously powerful scenes. Yes, she kind of got phased out of the story when Mullet Supes returned, but from her point of view, it was handled far in superior ways to Lois in "Doomsday" (except for visiting Martha)
QFT, though I think it would have taken a 3 DVD box set just to tell the full Reign storyline.
And there's no problem with that. Warner makes more money, the animators can provide fans with set-peices like Green Lantern vs Mongul, Superman and Eradicator in the Kryptonite smog. The action in "Reign" is amazing.