Back when I first played DX1, all the way back in 2001, I picked the Helios ending and felt it was the best ending choice out of all of them.
Over time, I oscillated between its ending and Tracer Tong's "man-made horrors beyond comprehension" take, before finally realizing that there's no putting the genie back into the bottle once it's out.
Helios may mean well, but for all intents and purposes it is an alien intelligence, and a complete unknown. We have no way of knowing what it will decide to do down the line (and it could be lying). It certainly does make a good arguments, but it also purports that making decisions based solely on cold, hard logic is the best way to govern, which didn't sit well with me, since I easily trace my way to the obvious end of that path - reason without empathy and morality to temper it never ends well.
Tong's decision to cast the whole of humanity back thousands of years technologically is no solution either - we'll either be stuck in the Dark Ages forever, or if we claw our way back out, all the cautionary lessons gained from stopping Page will have been forgotten, and humans will be poised to make the same mistakes all over again.
The Illuminati are not innocent, but at the very least they've prevented humanity from annihilating itself while they were in power, and with experience and wisdom gained from the MJ12 debacle, they can slowly ease humanity into an era of replicators and advanced AIs. I don't think they're the ideal choice, not by a long shot, but at the end of the day they are the least radical pick, and I'm perfectly willing to hedge my bets when it comes to the future of the species as a whole.
The really funny part is that most of the plot elements of DX1 come from late 1990s conspiracy theories. Little did the writers know just how much the internet schizos got right, and how they'd be vindicated in the decades to come.
Not to cast shade on the writing - for all the goofiness of some aspects of DX1, the writing is phenomenal. I recall people masturbating themselves into a stupor about the monologue the AI at the end of Metal Gear Solid 2 gave, despite the fact that DX1's Morpheus had a far more eloquent, concise and better written take years prior, to say nothing about all the other commentary about politics, religion, technology and humanity as a whole.
Most games can only dream to have as much well-written content, from dialogues to readables, as DX1 had.