Thanks for taking the time to interact with all of us! I think the emphasis on praxis that you value is actually right there in the major Pauline letters. He wrote to address on the ground issues that were affecting the life of congregations, not abstract theological treatises, as his letters have often been treated.
With that said, I think the stress that many place on the individual experience of the Old and New Covenants, while present in Paul's writings, are not the central issue. Paul seemed more concerned with how the gospel of Jesus was to bring people together, how the one God of Israel was equally the God of Jews and Gentiles... just as they were. The miracle of the New Covenant community was that former enemies were now sitting at the same table, with the walls of division now broken down. The former distinctions of race, religion, class and gender no longer made any difference because Christ and his Spirit did not recognize such distinctions, and their identity markers, as determining belonging to the people of God. Paul, in letters such as Romans and Galatians, fought against any effort to rebuild those walls, and divide the community along those former lines.
This is where I think that Adventism, and its entire reason for being, is fundamentally flawed. Our central focus on law/Sabbath/food laws, creates an exclusivity, and divides us from other Christians and Christian groups, over the very issues that Paul categorized as non essential matters... matters that should not divide. Link them together with an eschatology that says that the Sabbath will be the final issue that divides God's true people from all others, and you have a sectarian mind set and group that is totally at odds not only with the theology of Paul's gospel and the New Covenant, but with the practical implications of it as well, especially on the level of creating healthy Christian community.
While I agree with the necessity of action rather than more dogma, the reality is that ideas do matter, and that they inform and shape our actions. In light of the implications of the gospel and the New Covenant as seen in Paul's letters, I think that a fundamental reimagining of Adventism would be needed in order for a climate change to occur... a change that would provide a truly healthy and inclusive Christian praxis to take root and be lived out on a broader scale than isolated individual action.