Seems to me that the Reformed emphasis tends to be to look from God down to man, while the (Book of Concord) Lutheran position is to look from our perspective upward, always emphasizing the Scriptures over our own surmisings. The Achilles heel of Lutheranism is Justification by Faith. Once Lutherans turn away from this, the whole system breaks down into cowardly universalism (like UOJ) or antinomianism.
The Reformed problem at root is the separation of the Holy Spirit from the Word, and the emphasis on election. The Reformed Pastor can never know for sure if the Holy Spirit is present in a service. Nor can the consistent Calvinist ever know if he or she is truly saved.
Of course my bias is towards the Lutheran side, so take these observations as you will.
Most important of all in these late days is the joining together of those of like faith. There is such a spew of poison out there, that we must always treasure all we find with a “love of the truth” and a respect and submission to the preserved, eternal, powerful and efficacious Word.