My own inclinations here are that it would be good to have as few different technologies as possible. To run things on as few different machines as possible and to have automated tests for everything. The thing is that as soon as there are multiple technologies you get to have different people specializing in them and it is always the communications between those that becomes painful. The automated tests are there to prevent fear of change setting in. I think I am kind of advocating what is called a 'big ball of mud' but that I want it to be a transparent ball of mud because of automated testing. I guess what I am saying is that I distrust most developments in so-called application architecture of the last few decades except automated tests. In particular, I think frameworks and microservices are mostly just bad.