it is wrong to for subito to mean soon? °vengo presto a casa° o °vengo subito a casa° as interchangeable? Or does subito directly mean more immediate than presto?
I think that technically, it's "at once", but that's just another educated, Latin-based guess.
First, "I immediately come home" and "I come immediately home" mean the exact same thing in grammar and syntax.
Second, no English speaker would ever say,"I come ommediately home".