I actually really enjoyed it, the focus on the Doctor is a really nice change, and the way it scales down the Doctors bigger battles works very well.
That said I am left wondering something about the Doctor, exactly how up himself was his 10th self? for the whole "men who never would thing" it seems the Doctor is far from a stranger to doing something, ok I guess we knew this from the Time War, BUT 10 really over plays the other way around, the Doctor is clearly capable of loosing his best side when travelling alone.
This may have always been true, and its just that the 10th Doctor liked to deny it alot, pretend that wasnt the case. The show is also using it (and certainly talking about it) too much.
That said, with the focus on the Doctor, again it feels pointless keeping Amy and Rory around, when this could have worked with almost any companion.
The lack of female characters is hardly unsurprisingly in this, given its a Western.
As for the over all plan, it is basically giving Kahler a head start, but its not like the Doctor should not have suspect he may kill himself, but that was I guess his choice, as it was when he didn't step over the line the first time, after the Doctor stopped pointing the gun that is.