I actually thought it was a rather happy ending.
Seth moving on home (and I absolutely loved Swearingen's comment "it's to your right") and Alma seeming not just accepting but even eager to begin her marriage to Ellsworth tells us that they each will move on and have the potential to be happy.
Mrs. Bullock finding the seedlings her dead son planted was a bit heavy-handed but appropriate imagery. Of course we knew she would stay in Deadwood.
Cy's and Al's futures, barring any major (and corny) "shocks" are set: Al is the future of Deadwood. Note how differently the two of them started their relationships with Hearst:
- Cy only saw an opportunity for blackmail and a quick score, using unfortunate events in the past to capitalize on them.
- Al came to Hearst with respect, politeness and a plan of action for the future- both a solution to deal with an immediate problem (the Chinatown rivalries) and a sense of planning for the future of the town, as marked by his dealing with Yankton.
Note that when Al was ill, Cy had both Hearst and the Yankton comissioner in his corner. Now, due to his shortsightedness and impulsiveness, he has lost both. Cy's inherently vile nature oozes out of him and corrupts his business dealings, wereas Al can keep his darker impulses in check and channel them in ways that help or at least don't hurt his ambitions.
Wu slicing off his braid and proclaiming his loyalty to America and Al was pretty unreal.
I also love Al's disgust at the incompetence of his man after the first incident in Chinatown.
Jane at the wedding was funny- and Utter is back! Where the hell did he go?
One possible place they could go with Alma and Ellsworth is that now that they're married, Ellsworth has to learn not be subservient to her anymore. Given her temper, that could make for a tight situation.
We will also probably see Hearst battling for Alma's claim and therefore maybe learn more of the backstory as to why Ellsworth hates Hearst (remember it was that mistrust that led him to correctly advice Alma to keep her claim in the wake of the false rumours).
E.B. has gone from funny to downright disturbing. I actually hope we don't have another "main character goes crazy" thread like with the first preacher. And speaking of preachers- gutting Cy with a knife! Woa!
Someone else pointed out to me the poetic justice of him being punished by a servant of the Lord shortly after mocking his name during his extortion bid to Hearst.
I wouldn't be surprised if Wyatt Earp appears next season.