I found your questions and answers fascinating, the one about dreams particularly interested me. Your answer did surprise me a little since there appear to be some references to God communicating through dreams and visions after Jesus had returned to heaven. Such as Acts 16: 9-10. I would a love to hear your thoughts on this as this.
Answer
Thank you for not taking my comments without checking them. You bring up a valid question.
Some have argued for a late date for the book of Hebrews (probably just before the destruction of Jerusalem in 70 AD) and may use the opening statement as an argument that the miraculous gifts listed by Paul in 1 Corinthians were even beginning to disappear long before the death of all of the apostles. The problem with that is that John wrote the Revelation years later, and it was a vision, or included visions.
A second argument might be that the author of Hebrews is presenting a generalization that doesn't apply to the apostles (or, possibly, those to whom the apostles had imparted the miraculous gifts). Since the strongest arguments for authorship of Hebrews seem to point to one who is not an apostle, the "us" in verse 1 may include only the "common man." Thus, only those who were specifically gifted by the laying on of the hands of one of the apostles could receive a special revelation, while everyone else could not expect one.
Option three (and a very weak one) is that the vision of Acts 16:9-10 was not from God, but merely Paul's subconscious desire to expand the gospel into Europe manifesting itself in a dream or vision.
One other option, of course, is that I misused the passage entirely. Of course, I don't like that option, but I am biased. Taking that scripture out of the argument against God speaking to us in dreams today doesn't negate the argument. The limited number of visions and dreams (and they are apparently not the same thing) and the special and limited nature of the gifts of the Holy Spirit would seem to indicate that such communications from God ended with the completion of the New Testament as we know it.
Even if I misapplied the passage, one thing we can get from it is that any dream or vision today that contradicts the gospel of Jesus Christ as given in the New Testament is not a vision or dream from God. In that it is similar to Paul's statement in Galatians 1:8, "though we, or an angel from heaven, preach any other gospel unto you than that which we have preached unto you, let him be accursed." (Paul even repeated it for emphasis.) Unfortunately, some who claim to have a dream from God contradict God's word as well as other "dreamers."