I can see your points, to address them is not an easy task, but I will try. In my opinion, in the history of Marxist movement, Stalin by intuition is the one who arrived closest to the true dialectics, because he never let the abstract control him, but stayed with the concrete reality. However it necessary to remember Stalin can only see what historical conditions allow him to see.
The first problem is the concept of contradiction, what is it and when to realise the situation is in contradiction or not. We use the word "contradiction", because it is a relic of Hegel, for that he posited an absolute being with contradiction and from that generate a whole world (he was really a mad genius!), but as materialists and practitioners, we must identify contradiction in reality, when it's in contradiction, when it's not. It's not an easy problem, so I think I need to carefully research it before saying anything. Most of the time, contradiction is hidden or even not forming yet. In thought, and in social science, now it's easy to identify contradiction, but how about nature?
Diamat, from the existence of contradiction in thought, proceed to assume the existence of contradiction in nature. Why? Because Diamat holds the position that nothing is totally special, if there are contradictions in thought and thought is also a part of nature as other matters, then contradictions also must exist in others too. To find contradiction in nature, it is the job of practical engineering and science (I also list engineering, because most of the time, engineering is ahead of science), Diamat cannot do this job. However, without Diamat, the practitioners cannot identify the contradiction, because his philosophy forbids the existence of contradiction (metaphysics of non-contradiction). In modern history, Marx was the first one to success, as a social scientist, to identify the fundamental contradiction of our current society. To identify contradiction in nature, it's necessary to have enough data of its history, of which we are woefully lacking.
The second problem is about laws. What's law and its role in the world? Law is a governing principle for which matter must obey. But it is really true? Are Diamat laws something invincible, something cannot be violate? No, not true, but Diamat forbids that itself! So allow me formulate a really heretic thought, which I think even Engels, Plekhanov, Stalin and many other Marxist scientists somehow intuitively arrived at, but didn't dare to/or clearly expressed:
There is no such thing as concrete eternal law in nature. Every law must come into being from some basis, and disappear when its basis disappears. It's not Law that controls Matter in Motion, but Matter in Motion develops and expressed itself in form of Law. If there is a law, then there must be somewhere in universe this law doesn't hold, and sometime in the history this law didn't come into being yet. NO EXCEPTION. EVEN DIAMAT in concrete form. It's the development of nature, the development of material conditions that gives born to laws. Laws can influence, but cannot turn themselves against their material conditions.
So the true eternal laws must contain in itself all aspects of nature, both positive and negative. If "Nature Connected and Determined", then there is also an implication "Nature Independently Divided". If "Nature is a State of Continuous Motion and Change", there is also an implication "Nature is a Static and Unchanging". If "Natural Quantitative Change Leads to Qualitative Change", then also "Natural Quantitative Change Does Not Lead to Qualitative Change". If "Contradictions Inherent in Nature", then also "Nature Does Not Contradict Itself". And so on... But such eternal laws have no power over anything, don't predict anything, they are nothing but empty laws, for what Hegel correctly recognised, Absolute Being is Absolute Nothing. However, those laws are still useful, as they remind us of the true reality, that questions of cognition cannot be solved by speculation alone, but necessary by real, practical action.
Let take for an example, Newton's 1st Law: "An object will remain at rest or in uniform motion in a straight line unless acted upon by an external force" contain a hidden side to it, because there always exists environment, there always exist external forces, therefore "An object cannot remain at rest or in uniform motion, unless there is no environment." To recognise which side will apply, is the problem of actual research, which Newton's 1st Law cannot do for us, but only illuminate the way. I know at least one scientist is aware of this hidden side, and he had his own reformulation of Newton's 1st Law.
Or for example, the law of universal gravitation. If by someday, we discover the underlying material mechanism and conditions of this law, then we can finally drop the prefix "universal" and can find a way to escape the phenomenon of gravity. But this again, is a problem of engineering and practical science and not pure thought.
On the other points, which you talk about the importance of scientific method, and the criticism of Strong Emergence in the science of dynamic system, belong to the realm of concrete knowledge, so this I dare not to comment if I don't research them carefully, so I need sometime to prepare. In that time, could also clarify why you are against Strong Emergence and also the philosophy of Scientific Method?