What a mess

No kidding, and these are some of the things I noticed too. For me, first half of the season was interesting, but second half was pretty messed up.

Officials have no idea where the San-Ti fleet location is, so they think they can send a solar sail vessel whipping by at 1% light speed or 0.1 whatever it is and it will be picked up by the fleet which is moving much faster? The San-Ti are not omnipotent, yet officials totally expect them to pick up a tiny little vessel carrying Will's brain in the deep of space, just hoping they got the position and trajectory of the San-Ti fleet right... come on.

Tatiana is supposed to be a supernatural entity that can manipulate security camera systems, instead she's just some trailer trash living out in the sticks that is only being used by the San-Ti and just happens to be good with a pistol? What the heck?

When did they actually fly out and place the 300 nuclear bombs not to mention place them in such a position that it's aimed directly at the incoming San-Ti fleet, that no deviation can occur whatsoever. No government in the world would ever give 300 nuclear weapons for a project as convoluted as this. Then they have to detonate the nukes 300 times hoping that not a single problem will happen? Ridiculous.

Wade orders the deaths of over a thousand people living on the Judgment Day ship, children, men and women, families, scientists, etc, and this isn't a problem? Where's the morality? What they did to those people is pure evil and worse than anything the people on board ever did.

They're hoping that Will can be reconstructed from his brain by the San-Ti, but what will emerge is not Will, but a clone. Will died the moment they took his brain out of his body, there's also the soul to consider which this show conveniently ignores.

Season 2 is gonna be weird, I wonder if they will time jump because 400 years is a very long wait.

I'm toward the end of the book and I will pass the show, because... well, the book is lame and even dumb. There are a couple of cool ideas, but apparently the author was not fully aware or not able to develop them properly.

But about your question - their travel time is 400 years, because they travel at fraction of the speed of light. The aliens themselves are situated in Alpha Centauri system, which is 4 light years away. This is accounted for in the book.

Speaking of Alpha Centauri, there are three stars there, but in stable and predictable orbits, and one of them is too far from the other two, so you certainly won't see three suns in the sky of any planet there. Apparently when he researched the book, the author didn't bother going beyond the first few lines of the relevant Wikipedia entry. But the factual errors are the least problem. It is just that everybody is dumb and makes no sense, including the aliens.

Presumably the helmets were made by the sophons, but if they were, why can't the sophons also just kill off humanity now, and not have to worry about humanity catching up with them technologically? But of course, the aliens have a plan, and it involves some of the characters... rolls eyes

did you actually watch the show or are you just not paying attention?

"Tatiana seems to be a super natural entity,"

she's super trained but not supernatural. The "supernatural" are the sophons.

"Aliens are 400 years away, yet they can communicate instantly with earthlings."

If I drive to LA I might be 2 hours away but I can communicate instantly with my friends in LA.

Their ship travels at 1/100 speed of light iirc and the instant communication is trough the sophons and quantum entanglement (I know, it's usually considered that instant communication through QE is not possible),

"A response to the alien signal is sent in the 70s and apparently reaches a few light years away instantly"

Actually no, it's not instantly, and the response took years to reach us. Message sent in 1968 and response received in 1977.

"Aliens can deliver mail (helmets) across the galaxy apparently faster than light,"

Actually they only delivered the plans on how to build them, not the helmets.

"There's apparently an alien VR game to challenge humans to solve the alien 3 body problem. This has little to no relevance to the story and it's a major distraction."

The game challenges humans to solve the 3 body problem and it used as a brainwashing device with subliminal messages and to make the people that play the game more sympathetic to the aliens' situation.

I actually think one of the biggest unforced errors was when they killed Jack Rooney. That was unnecessary. Dude just thought it was a con. Had no plans to do anything. So they kill one of Jin Chengs best friends in a quite obvious assassination and don't expect blowback?