1. The philosophical basis of our physical theories is a very well studied problem. The reason you don't see it in common parlance is that most of us, even most professional physicists, are not qualified to talk about these issues in detail. For stuff you have not seen, you need to dig deeper into literature. Its all there - I am not qualified to point to a good resource.

2. Physicists are always happy to consider all sorts of theories. Problem is that any new theory must also retrodict all known experimental results as well as make new predictions. The reason you don't see better theories than QM is that we physicists have failed to be creative enough to think of a theory that is better than QM at prediciting experimental results. When we do, or when you tell us a precisely defined mathematical model of reality that is better than QM at predicting reality, we will throw away QM like a burning brand and hop onto the philosophical bandwagon of the new theory.