There is little need to worry about the stars they just increase with your post count, the colours too aren't worth worrying about as the UserName usually has some other profile information below it, those with Alwil Team or Moderator are developers of the avast anti-virus.
An Überevangelist is probably someone with way to much time on their hands
I can't recall if it was 20,000 or 25,000 post, which is unimportant really. What is important is the content and help you receive from whomever it is, be that a Newbie or an Überevangelists as that only relates to posts in the avast forums and not experience in the real world.
There are some very experienced avast users, who when they first join are Newbies, but that most certainly doesn't equate to their experience.
By the other weird icons I take it you mean those below, see image
