Whilst I agree with your observations I also think the really successful teams may change tactics for who they are playing but not because it’s simply home or away - why should they? - ok the pitch may play a little differently but they are meant to be professionals - as for home vocal support, well that’s complete rubbish as we get much better vocal support at away games than the sixfields library. For me a manager who consistency plays a different (ultra defensive) game away from home is one who will at best achieve mediocrity and has an aging 30 year old grasp of tactics.
I think the vocal support is similar in terms of people. It’s just that at away games all of the vocal people are generally sat together under one (often fairly small) stand as opposed to being split by the stands (e.g. north stand/west stand).