I do believe in an after life and I believe there are people walking the Earth right now who have temporarily visited there. I have a long list of questions I haven't been able to answer to my satisfaction over a lifetime and that's the one thing I want to take with me when I go: that list so I can get those questions answered.
I agree that heaven is not flowing robes and floating around on clouds strumming little harps. That sounds a bit grim to me too.
I don't really know what to expect except that I do expect to see people I know who preceded me in death. And I am looking forward to that.
And I expect to see people I have known only via the media or in history books, and I think those will be fascinating to have a conversation with. I don't what what sorts of things there will be do there but I do expect to just step from this life into that next one and live on. There will be things to see. Things to do. Things to learn. Hopefully without the negatives we have here.
Nobody who has been there reports it as an unpleasant experience in any way. No one who has been there doesn't want to return there.