I think the question in its current form can be read both as a research-level question and as a theoretical computer science question (computability), but not both at the same time.
The research-level question would be more of an Software Engineering type I think (with emphasis on Engineering), particularly because the you are asking for heuristics (the algorithm doesn't need to output the correct complexity on all inputs). Generally finding heuristics engineering solutions for problems that are undecidable from theoretical viewpoint are mostly a topic in software engineering.
You may be able to modify the question to turn it into a research-level question in TCS, however I think the more natural way of asking the question which is close to your intentions is asking for heuristics algorithms used by people in Software Engineering/Formal Methods.
Someone from that Software Engineering/Formal Meothods can answer the question way better than people we have here IMHO. Anyway, this is just my personal and which is not a strong one (I haven't even down-voted the question).
Regarding the second part, I agree with Tsuyoshi. You should read each site's FAQ and a few question with tags similar to the one you are going to use on each sitethem to understand their scope and which one is better suited for your question. Each site has a different community and the answers you get can vary considerably because of that. Look at the answers people have given to similar questions on them and see which type of answer you are looking for.