A paper closely related to my recent translation on lay elders is the following:
Collver, Albert. “Lay Elders-A Brief Overview of Their Origin in the Missouri Synod: Implications for Elders Today.” CONCORDIA JOURNAL 32.1 (2006): 38.
It is available here: http://bit.ly/1QuSrKE.
To be clear, I was unaware of this paper until after I completed my translation. The paper is a historical review of material published within the Missouri Synod which treats the office of lay elder. Collver spends over four pages discussing Walther’s 1858 Lehre und Wehrearticle. In doing so, Collver certainly does not accept Walther’s justifications of lay-elders uncritically. After treating this material, he goes on to summarize material from other works of Walther, namely Kirche und Amt  and Die Rechte Gestalt  where lay-elders are mentioned. And he finishes his article by examining work published by Theodore Graebner in 1915 and 1916 (and then again later), who desired to present and augment Walther’s argument for lay-elders to the rapidly changing WWI and post-WWI Missouri Synod which was in the midst of changing primary languages.
In between the Walther and Graebner material, Collver usefully documents public disagreement expressed by Dr. Charles Krauth of the General Council toward Walther’s justification of lay-elders. A report is quoted by Collver from the Oct 22, 1874 issue of The Lutheran and Missionary which summarizes the disagreement and presents at least two counter arguments to Walther’s position.
Collver’s article is useful as a historical summary. And it is primarily intended to introduce the Missouri Synod historical sources. But Collver’s article proceeds to offer some historical and theological analysis of some of Walther’s arguments. And here it loses its way in between roles and offers only a partial analysis of a limited selection of Walther’s arguments.
Collver notes that in Walther and Graebner’s presentation regarding lay-elders or ruling-elders, 1 Tim. 5:17 is “the lynch pin passage.” . But he dismisses their exegesis of the passage stating it is different from Luther and the church before Luther. Walther’s exegesis is the exegesis of Calvin. However, ultimately he concludes that since Walther and Graebner, unlike many of the Reformed, view the office of lay-elder as a matter of freedom and not a divine requirement for the church, “we need not agree with Walther’s interpretation (of 1 Tim 5:17) to retain, utilize, and be thankful of the lay elders who serve in our congregations.” 
At a minimum, Collver uncritically accepts and presents wide sweeping historical statements about the pre-Lutheran exegesis of 1 Tim. 5:17 without providing any proof. In doing so, he simultaneously very lightly dismisses all the opinions of the Orthodox Lutheran authorities produced by Walther, primarily on the basis that they are neither Chemnitz nor Gerhard as if these are the only serious Lutheran teachers to be concerned with post-Luther. And so Collver ultimately rejects the exegetical argument Walther offers for the historicity of lay-elders. I emphasize again that Walther’s usage of 1 Tim. 5:17 was as a historical witness that such lay-elders existed in Pauline congregations, not, as with some of the Reformed, as proof of a divine or apostolic mandate for the necessity of such an office. And in that point Collver ultimately tries to find common ground with Walther as noted above.
In dismissing 1 Tim. 5:17 as a historical witness, Collver skips any other historical arguments dealing with the next 1500 years, and gives the impression he supports the interpretation that “lay-elders” or “ruling-elders” were an originally Calvinistic innovation later accepted by various (but few) Lutherans and then ultimately by Walther. In taking this position, Collver does not address at all other arguments presented by Walther based upon similar ecclesiastical roles for laymen in the church as shown by the German consistories or some of the specific German church orders Walther produces. Nor does he address the patristic material Walther offers.
Indeed, one might say that the choices of analysis Collver chooses to offer and not offer may more reflect the spirit and strengths (and weaknesses) of the Missouri Synod as much as it reflects any fundamental weaknesses in Walther’s argumentation. But that would be a bold assertion on my part.
Having said all of the above, I can largely agree with Collver’s concluding remark that:
Walther’s introduction of lay elders to the Lutheran church in America was not based on particular Scripture passages that instituted this office; rather, it was based on the church’s freedom in Christ. Walther’s teaching on auxiliary offices formed the basis for the lay elder.