I love the original Ghostbusters, but as the sequel and the remake proved- just leave well-enough alone.
The first movie mainly worked because of the new computer-gadget craze that occured in the 80's. We were still learning about computer technology, so anything that showed smart people using clever gadgets was fascinating. A lot of the movies and TV shows from that era had a similar premise: rag-tag heroes using technology nobody else has knowledge of to fight evil. We saw this in Blue Thunder, Knight Rider, Airwolf, and countless others.
People today are jaded with technology. We can turn our lights and appliances on with our voice, we have all human knowledge available from a screen in our pocket, we're shooting things into space on a whim...that kind of thing doesn't excite as much as it used to.