Season 3 feels like the end of Homeland - hope they don't just play out the string

Though I realize that the critics were less than kind to Season 3 of Homeland, I found the season to be very compelling and dramatic, the final episodes, which bring Brody, trailed by Carrie (Claire Danes) into Iran on a mission of assassination, to keep up the tension from the earlier episodes and even build up the drama. As noted in previous posts, Danes is terrific and expressive throughout - her face has to be the most expressive in all of television - and the rest of the cast is generally very good, notably Patinkin, who despite is mannered mumbling which causes us to miss a few lines here and there, has really grown into and developed his role as interim CIA chief (F. Murray Abraham, on the other hand, is really miscast - who knew two old Jewish guys ran the agency? - and perhaps as a result the season makes less of his devious nature than it could have). The plot in this season is particularly complex, but as we follow it we are always rewarded with surprises - and all told the complex plot seems pretty credible. (I won't divulge any of the surprises here, btw.) On the other hand, the weakness of the season and of the series in general is the relationship between the principals, Carrie and Brodie - I just can never buy that they're so deeply in love with one another - each is too driven, too professional, and finally too different to imagine them having any kind of life outside of the life-and-death drama they're caught up in. I think a weakness throughout has been Brody's family, which the creative team seems to have realized, too, as they have moved wife and son largely offstage and focused more on his relationship with his daughter, a truly fine young actress I believe. It feels as if the series has reached a concluding point at the end of Season 3, but evidently not as 4 is being aired and streamed right now; I will watch, no doubt, but am always troubled by great series that seem to run on a season or maybe two seasons too long - can anyone say The Killing? A great series really does not a sense of an ending, and I hope they don't just run out the string in succeeding episodes.