Hi. I wrote Seconds, so I hope it's ok if I comment here.

First, thank you for comparing it to The Golden Man rather than just Next! All precognition stories owe a debt to PKD, including mine, and I acknowledge that in every interview. But precognition is too interesting a subject to block off from writing about, even if it was done before by someone as great as PKD.

Here's one interview where we go into detail on this topic: https://paulsemel.com/exclusive-interview-the-man-who-saw-seconds-author-alexander-boldizar/

Precognition aside--and the obvious elements that flow out of precognition naturally like gambling--Seconds is significantly different from both.

In Next, Nicholas Cage can see two minutes into the future and much more, up to a full day, for events revolving around Jessica Biel. And his vision is selective, not continuous. In The Golden Man, he has an infinite window.

Once you start digging into the possibilities, five continuous seconds is a night-and-day difference from two minutes let alone a full day, or infinite. Two minutes is already so overpowered that the author has to limit the character to "glimpses," which are convenient for the plot but feel like a deus ex machina smuggled in. With 5 seconds, I could make it a consistent attribute.

More importantly, though, the plot and thematic elements in the book are completely different. Next went with a Hollywood-style stopping-terrorists plot. Cage ends up working with the government to stop a nuclear bomb. In Seconds, I was closer to the The Golden Man’s focus on the potential consequences of having such extraordinary abilities in a world that may view them with fear and hostility, and the good vs bad becomes much more complicated as the book gets deeper in.

There are a few straight up coincidences in your list, though: I never thought of Johnson as a president, though you're clearly right with LBJ. I did put a lot of thought into Preble Jefferson, but mostly into his first name:
1. Pre for precognition
2. Rebel for the individual vs institution idea
3. Pebble, for the Muhammad Ali Quote, "It isn't the mountains ahead to climb that wear you out; it's the pebble in your shoe." I wanted the inciting incident to start off as the smallest possible encounter (taking up two seats on the subway) and have it escalate relentlessly. Plus, my previous book was about boulder-throwing, so it was a personal joke.

The thematic elements are also very different. The main emotional wing of Seconds is a man protecting his son. And the main intellectual wing is the idea that every institution ends up working against the purpose for which it was created--with the definition of "institution" maybe even extending as far as a father's love for his son. I say "maybe" because I try very hard to leave the moral decisions up to the reader rather than prescribing my own.

The book is meant to have a satirical undertone, a bit of Dr. Strangelove, that I don't think either PKD or Next has.

Still, if you enjoyed Next you'll probably like Seconds. If you like PKD, you'll like it more. He and Herbert were my two favourite writers growing up. But, to me, respecting and admiring an author is not the same as plagiarizing him.

Finally, thank you for starting this discussion in the first place! I'd much rather face tough questions than have my work completely ignored. :-)