Let me repeat in hundredth time. There are so many different technology flavors that is impossible to make all prerequisites sensible.
I think I managed it in my latest mod version 1.43 tech shuffle. I definitely had some trouble in the vicinity of Self-Aware Machines, but I eventually found a solution. There are basically 2 kinds of continuity: research continuity and narrative continuity. I
prefer research continuity, the respecting of Explore Discover Build Conquer categories. I don't like it when I've come up with only a narrative continuity, and the research categories don't basically make any sense one after the other.
Besides it almost never sensible for one color to be dependent on other color.
This is false. Techs can be legitimately cross-listed in multiple categories. This requires a clear and consistent criteria for what different color categories represent. For instance in my mod, Explore green color represents happiness, growth, exploration, and indigenous life techs. This is quite overloaded, but it's not my fault. It's what the original game implemented. The only controversial change is putting happiness in with Explore. I think it's an obvious consequence of growth, you can't grow if you don't have people happy. I decided that Build is going to be about minerals and energy, wealth only. You can be happy and poor. You can be rich and miserable.
Over time, I decided that strict separation between Explore and Build is not generally valid. For instance if you have more workers, you're always going to make more money or minerals. Yet I don't want every research category to mean or imply every other research category. So I adopted a "half as much influence" doctrine. For instance my Social Psych gives the Recreation Commons. I assign it growth=4 because it's making people happy. I assign it wealth=2 because having more happy workers
does make one more money or minerals. And because I want happiness facilities to be primarily in Explore, not Build.
Yet you have to do it.
Generally speaking that's not true. However, I do make abrupt "cliff" transitions when I actually
don't want it to be easy to get from one tech to the next. It is possible to delay and semi-hide techs from being researched that way. I used to treat fusion reactors and genetic warfare that way. Lately, I'm not sure what's happening. I've had to change the categorical continuities around for other reasons.
Were you able to quickly memorize whole tree?
Some orderings and transitions make it easier or harder to remember than others.
I never was and it never bothered me.
That doesn't speak to the point of whether or not it bothers
others. Being aware of one's own biases, is important when designing. It's not essential that you take other people's point of view into account, but failure to do so, can affect adoption rates.
For instance, the author of Dwarf Fortress is known to be autistic. He likes the ASCII text, labyrinthine menus, and extensive keyboard chord sequences to do things
just fine. Although the game has had design influence, and has some notoriety, and even a sustainable business model, it's
clearly not as popular as it could have been. This is because of the author's blind spots about what doesn't bother
him, vs. what does actually bother a lot of other people. And apparently,
RimWorld has subsequently become the better title? I haven't really played either TBH.
"There's no issue" is a very different argument from "there's an issue, but I don't want to work on that, because I think it's too expensive for me to do."
Were you able to memorize Civ 1/2 tech tree even if it was supposedly reflecting a real technological progress?
Yes. But it took time, perhaps measured over a timespan of like 3 months of seriously incessant full time play. I had just quit my job...
Was everything sensible to you then?
Pretty much. The tree
was grounded in when historical inventions actually appeared, more or less.
How the hell you can develop Medicine from Trade + Philosophy? 😲
This was one of the weak spots, as it didn't respect any kind of indigenous practices of "medicine". Everyone's had some kind of medicine, and some of it worked better for some things than Western medicine.
How the hell Space Flight was possible without Plastics in Civ 1? Oh well.
Not sure I understand why you think plastics are essential to space flight. But this is going sideways into a discussion of our knowledge of real tech history. SMAC of course isn't real tech history.
For one we can just darn rename them all and repaint tech tree from scratch!
I rarely do this to techs, but I have done this in a few instances.
For instance, I changed "Frictionless Surfaces" to "Single-Sided Surfaces" at one point, because I was trying to figure out a valid fiction for a Clean Reactor. I was moving things around in the tech tree and trying to repurpose the techs, without violating the quotes and voice acting that were inherently stuck with the tech. I decided that these lines were vague enough that they could be about something other than friction, this idea of "hiding a surface from itself". That a Clean Reactor could be some kind of conceptual Mobius Strip. It held up reasonably well at the time.
Well, my tech tree changed over time.

The Clean Reactor went elsewhere. I decided the Single-Sided Surface was going to be my hand wavy explanation for how the 3-Pulse armor works. It doesn't make a whole lot of sense, but hey, it's tech! The real reason I kept it, is because I'd put my "personal stamp of style" into the game. I didn't feel like taking it out. It's one of the ways you can tell I modded this.
I have Phasers instead of Fusion Lasers. Having Fusion as a name for both a weapon
and a reactor is damn confusing for automatic unit names, so I abolished it. It is obviously a nod to Star Trek.
I have Chronoton Guns instead of Quantum Lasers. Again, having a weapon and a reactor sharing a name is confusing. This is a nod to a Star Trek Voyager episode about "temporal incursions". The weapon is given by Temporal Mechanics. The next tech gives Graviton Guns, so there's a phonetic continuity.
Most recently, I have renamed "Orbital Spaceflight" to "Orbital Construction". Also "Advanced Spaceflight" is now "Orbital Supremacy". They're also both much later in the tech tree. This is to better explain what a Sky Hydroponics Lab is about. It's required to be the 1st available satellite if you want the satellite UI to work properly. Planet Busters and the missile chassis are not required to have that UI work, so AFAIAC now, those missiles no longer have
anything to do with space flight. We can launch terrestrial missiles just fine without going into space. Such things are generally called cruise missiles. Indeed, they got called that in later Civ games. Orbital Supremacy gets my Orbital Defense Pods and Geosynchronous Survey Pods. The choice of name is a nod to the old board game [Supremacy](
https://en.wikipedia.org/wiki/Supremacy_(board_game)). It is also something that militaries actually try to achieve, i.e. Air Parity, Air Superiority, Air Supremacy.
The challenge in all of this, is to try to utilize and
respect the quotes, narratives, and world building that are already in place.
Sometimes I've welded a tech and a Secret Project together, because the right character was talking about stuff. For instance, Chairman Yang yabbering on and on about how to overcome yin yang dualism. He does it for Monopole Magnets. I decided that's a good place to weld the Ascetic Virtues. It's not a perfect tech relationship, but it's a good
narrative relationship. I happened to want those things to come at about the same time, in the beginning of the midgame at my Tier 3. They were floating around each other, and they helped me solve some narrative and tech fitting problems at the time. I don't plan to take them apart again.
As it doesn't affect game play I don't pay attention to it much. You are welcome to team up with me on it. I hear a lot of critics on this specifically but nobody volunteered yet.
😉
Well as you know, I'm not teaming up with
anyone to solve such problems. I do my own mod to toot my own horn as a game designer. Being deft at such rearrangements, respecting the previous
quality of SMAC as a narrative work, is part of what I do well as a designer. I have my own specific tech tree results. I merely suggest looking at what I did in my tree, when contemplating such problems. Because frankly, I've done a better job of it, by far, than anyone else's work that I'm aware of. If someone did some bangup job of this sort of thing back in the stone ages of SMAC modding, well their work hasn't survived in anyone's mind in the present day. I
suspect that I'm the only person who has put 2+ years into these kinds of "narrative and technical and balance" rearrangements.
Direct lifting of my tech tree, requires attribution per my CC-BY-NC license.
Inspiration of course requires nothing. I hope to at least inspire.