I think most JW's have vague abstract notions about Armageddon, Paradise and what living forever would be like. I think the main concern for them is not growing old and dying and or not being destroyed at Armageddon. I don't think they think about it in any real detail, they just fill in the blanks with whatever soothes their own personal fears and makes them stop thinking about reality in general...especially the reality of what they say they believe. On some level they know that thinking about it too much will be the death of the magical illusion that keeps them buoyed psychologically.
For me, I was more concerned about the "GREAT TRIBULATION" and how I could possibly remain "faithful" while being tortured, which we were assured would happen. One of my big childhood fears was that during the tribulation "THEY" would threaten to injure my little sisters if I didn't "renounce my faith. How could a 10 year old boy possibly stand firm while witnessing his little sisters being tortured and why would anyone care if I lied and said I didn't believe in Jehovah anymore, just to keep save them. Then I'd hear them talk about Shadrach Meshach and Abednego the Hebrew boys who stood firm and were thrown into the fiery furnace. I always wondered what happened to them after that. Surely they went on to live noteworthy lives after having survived being thrown into a furnace. What was this furnace for and how come those boys were never mentioned again in the Bible. Was that the highlight of their life?
Anyway, I figured that if I could get through the TRIBULATION, the rest was up to Jehovah and there was nothing I could do about that part of it. I only hoped that I wouldn't die from being tortured or at the hand of Jehovah at Armageddon because not only would it be really painful but it would also mean I could never get married and have a family. This was a pretty sick way for a child to grow up but that's how it was and there's nothing I can do to undo the damage it has caused me.