If these are your ideas of plotholes, then you're misusing the term. Perhaps you'd like these things explained more in depth, and if that's the kind of storytelling you prefer, then that's fine. But nothing about any of this (except maybe #1) actually doesn't make sense or go against any of the world's rules.
Then let me address this before going back to tackle the actual points, because I really don't think I'm misusing the term at all.
To quote Wikipedia (which admittedly isn't perfect but I think this definition is reasonable): A plothole is a gap or inconsistency in a storyline that goes against the flow of logic established by the story's plot. Such inconsistencies include such things as illogical or impossible events, and statements or events that contradict earlier events in the storyline. I would also add onto that things that contradict plain, common sense, but I suppose you're welcome to dispute that addition.
Now, you can argue whether my arguments are right or not, but if you do accept that my argumentation is correct, then I don't see any way that you cannot consider these plot holes. If Snoke's origins make no sense given the lore that was built up in the prequels, that is an event that contradicts earlier statements in the Star Wars storyline. If the force acts inconsistently compared with previous films, that is a plothole, because it contradicts how the force is shown to work previously. Etc. etc.
To the other points:
1) I feel like this is a pretty significant stretch, especially if Leia is unconscious. Admittedly what the force allows its users to do is so vaguely defined that it's hard to say what is or isn't feasible, but I think you'd see more usage of that in the series. A field that entirely negates the vacuum of space would have to be pretty strong, and it seems like it would have been used before.
2) I guess I missed that explanation, but it just backs the plot issue up to a previous point, i.e. Snoke's origin. But more on that in Point 5.
3) Given that not five minutes earlier a Resistance fighter crashed her ship into a friendly ship to stop him from taking out an enemy cannon, and only an hour ago had two coups back to back, I don't think the kindergarden label is inaccurate. And, again, why take the chance? The resistance is scared, many of their members are clearly not thinking very straight, and they're backed into a corner. They're probably not in the best state of mind. Why would you assume that they would be thinking logically when you can just, with a single sentence, ensure that they get what you're doing?
And the idea of Luke just acting erratically is a poor excuse at best. If he was capable of formulating a plan like that and having a last, meaningful conversation with his sister, I think his mental condition was intact enough to simply say "Hey I'm stalling them, make a run for it."
#4: Maybe I missed this, but...when was it mentioned that Qui-Gon developed the technique? At the end of Episode 3, Yoda talks about communicating with the dead, but that doesn't seem like the same thing. And, on top of that, it brings up another issue...
#5: If Snoke wields this long-distance communication power which, according to you, was exclusive to Qui-Gon, Obi-Wan, Anakin, and Yoda, then where did he get it?
The knowledge of the Jedi and Force was pretty much reduced to myth status, if A New Hope is anything to go by. Han disregards it as superstition when he first meets Luke and Obi-Wan.
As for other individuals, granted, there are plenty of force sensitive people. But Snoke, even if he isn't explicitly stated to be a Sith, is very much skilled with the dark side of the force. That takes training, and there aren't exactly a ton of people who are offering lessons in force wielding out there.
Again, why this all matters is the stakes that the universe operates by. If your universe is filled with gaping plotholes, then it's just inconsistent. To quote my previous post: "The less consistent your universe is in operating within the parameters it sets for itself, the less believable it becomes. And the less believable it becomes, the less reason I have to care about any of the stakes in these movies. If these all powerful force beings can just spring up out of seemingly nowhere, why should I care at all about what happens to Rey or Kylo? Who's to say that another highly skilled force wielder that we've never heard of and is only appearing now for some reason won't just suddenly pop up to save/destroy the galaxy next? Who's to say that there isn't some other force sensitive kid who will pop up out of nowhere to save the galaxy? When you discard the rules that you set forth for yourself, your universe becomes an utterly arbitrary place where anything can happen for the sake of whatever plot device seems coolest to the director."
1. Again, without seeing the scene again, I can't really comment much further. It depends how long she was out, and I'd still have to double check to see if it was her or Kylo doing it.
2. It was very explicitly stated.
3. I think it was made clear that Finn's plan was not going to work. I'd also have to watch this scene again, but it didn't seem like he would have made it there, as his ship was already melting on the way. I'd have to see the scene again, but I'm fairly sure the implication was that he was playing hero for the sake of playing hero, and Rose saves him from an ultimately doomed plan.
As you point out, Luke had a meaningful conversation with his sister. And what did he say in that conversation? He said, "nobody is ever gone" (or something to that effect) before giving her Han's dice. The implication is obviously that people live on in our memories. Why give her them at that moment? Obviously, to let Leia know that he doesn't plan on making out alive. It's a more subtle, more aesthetic, and more memorable way to express his plan.
Leia knows Luke doesn't intend to make it out alive. So, what exactly would she have done? Luke can trust that Leia has common sense and is going to figure leave. And also, let's keep in mind, that Leia is literally the only person there who Luke knows and is the leader of the resistance. It would be weird for him to strike up conversations with a bunch of new folks.
I'm not saying it wouldn't have made more sense to say his plan explicitly, because it would have. It would have also been far less interesting. What was done still falls well within the realm of suspension of disbelief.
4. In the end of episode three, after Yoda says this, I'm 99% sure Obi Wan name drops Qui Gon. But, whether he does or not, it's clear what they're talking about. It's the very end of the prequels, so there's not going to be any payoff in that series, which means they're referring to something from the originals. Since the force apparitions are the only thing we see that relates to communing with the dead, that must be what they're talking about.
5. I never said that was exclusive to them. Neither Anakin, Yoda, or Obi Wan seemed to have the ability to communicate directly over a distance, aside from being dead.
Where does he get the ability? By practicing I guess. I'm not sure what you're expecting here. Are you looking for something like Naruto, where they introduce a new technique, and then have a 20 minute flashback for making of the technique? Like, a scene of him meditating and practicing telepathy? If that's the kind of storytelling you prefer fine, but that doesn't make this a plothole. If we did it that way, they'd never be able to introduce any new kinds of force techniques, like force lightning, in Episode VI which was also introduced suddenly and surprisingly. We haven't seen every potential force ability yet, and only a few that involve the dark side.
We also don't know that other people can't do this. It's not a particularly useful technique. They already have the technology to communicate over long distance which is far simpler. It's only used here because the Emperor is using it to draw Rey to him, and because Rey and Kylo have a special connection. But it's not like a replacement for cell phones.
Jedi being a myth makes about as much sense as the 1960s being a myth to us. Luke was born at the end of the Clone Wars, and he's in his mid 20s by the end of ROTJ. There have been 30 years in the interim, so we're at most 60 years removed from the Jedi order being a pretty big thing in the galaxy.
At the beginning of a New Hope, there are people alive who have seen and interacted with Jedi. Leia's father is one, and Jabba is another. And when Jabba coins the term "Jedi mind trick", no body seems to doubt Jedis are an actual thing. In Rogue one we see that there is a whole sect of monk like people who know of and use the force. A random smuggled may not know, but the even if there was a concerted effort from the Republic to stifle knowledge of the Jedi, it would have been nearly impossible to do so.
It's never stated, but Snoke's design definitely conveys age. He was quite likely alive during the Clone Wars. It's not unlikely at all that he'd have access to information regarding the force.
You repeated yourself again, but these still aren't plotholes. Some of these things actually were clearly explained but you missed the explanation. The one you keep coming back to is Snoke, but that's based on the faulty assumption that in a galaxy of millions, there can only be two people utilizing the dark side of the force, but that is never stated. It in fact seems highly unlikely that in a galaxy of at least millions (presumably trillions) there would be only two people.