As an ex-Christian I find it amusing that you chose to explain via parable. :)
However, I think there are some flaws to your story. You seem to assume that Heaven would be like getting permanently sealed into your own personal holodeck, alone, no contact with anyone but the entity that put you there, the computer loaded with complete records of everything that had existed up to the moment of your death but never updated beyond that. It's all so very static. Of course you would eventually go mad; what you're describing is just a more comfortable version of solitary confinement!
It's also not how Heaven was described to me when I still went to church. Some claimed we would all be sitting on clouds singing praise songs, forever experiencing a state of mindless ecstasy. (Which doesn't sound like much of an improvement.) Others claimed the Bible says we will be rulers in Heaven, and how can you be a ruler without something to rule over? (That seemed a little better, but I also don't really want to be some kind of king imposing my will on others.)
The most appealing concept of Heaven I've encountered so far is the one portrayed in the Housepets! comic. It's just another place, but one where everyone has agency and security and has been healed of whatever traumas ailed them in life. They are free to build, create, share, and grow as they like. You can still fuck off and become a hermit if you really want to, but most people choose to hang out in a big city. Some have jobs but there is no money or material needs; they work because they enjoy it or because they believe it's worth doing. One of the characters even chose to open a free massage parlor because they like helping people relax and wanted more opportunities to do that. And the mortal world still exists, so there are always new people to meet and new stories to read (or write!)
I could maybe spend eternity in a place like that. And if I had to change to make eternal existence possible, well, I'm not the same person I was five years ago and I have no desire to still be the same person five years in the future. I think if Heaven did exist, then Purgatory must also. Not as a place of punishment, but of healing. This world will crush your soul, and even the purest of saints (perhaps especially the purest of saints) carries too much pain and trauma with them for any place they exist to be a paradise. I think you're right that in order to be okay with eternity we would need to be changed into something unlike our current selves.
Sorry this got so long and rambley. I've spent a lot of time wondering what kind of hypothetical afterlife could possibly make this all worth it.
I made .iso files and mounted them in virtual drives to do the same thing. I could have used cracks but I didn't want a virus and I still had the delusion that doing things "fairly" actually meant anything.