When I was pulpit supply (before I was ordained) some years ago, I preached through Hosea. I was rewarding in some ways, but I realized I should not have tried to preach through any minor prophet, let alone the longest one, as such a greenhorn.
Essentially, preaching through a prophetical book is preaching on preaching, or preaching someone else's preaching. I consider it to be one of the most challenging aspects of anyone's preaching ministry.
It wouldn't be bad to preach a short series on a prophet as a young preacher. It would be very good to preach occasional sermons on particular texts, and gain valuabel experience in this kind of exegesis, analysis, and preaching before attempting a major undertaking in this kind of literature.
And then, make a careful selection of what and where to take it up. Much, indeed a tremendous amount of this material, is judgment and condemnation. Most of it was preached to a religiously backsliding people, to a church drifting or plunging into apostasy. There are important words of comfort to the faithful remnant and the repentant. But preaching that powerful judgment to your congregation week after week may be hitting them with something they don't need as much as something else. Then again...
Now, perhaps in a lecture format/Bible study setting, you can be more explanatory, analytical, social-relations oriented, etc., and your hearers will certainly benefit. To directly answer the question, "Why don't we hear more preaching on this material," I would say there is a measure of wariness on the part of many preachers, and perhaps too much of that.
The choice of text (or texts in series) ought to be a careful matter, and very much attuned to a specific congregation's needs. But as a preacher or a teacher, you will miss some of the richness of biblical content if you ignore these books as well.

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Rev. Bruce G. Buchanan
ChainOLakes Presbyterian Church, CentralLake, MI
Made both Lord and Christ--Jesus, the Destroyer
Acts 2:36 - 1 Cor. 10:9-10 & 15:22-26 - Hebrews 2:9-15 - 1 John 3:8 - James 4:12
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