half of those are absent in Traveller.
Traveller has as a line a large number of Aliens. None in the CT core, but by 1981, several were published humaniform but clearly not human.
Meh, I know of little to no material that deals with mixed-race culture, few materials and adventures that really deal with aliens in any substantive way. Yes, they technically exist, but none of Traveller's alien races ever amount to much, and there were no provisions at all in the CT core, as you point out, which WAS the game for quite a long time, and remains the default "build random subsectors" model even today.
There is no single dominationg galactic power. official maps of the Imperium are about 320×512 parsecs, the imperium itself is about 220×200 Pc. The Aslan hierate is 224×120 (triangular). The Zhodani Consulate is 120×120, roughly rectangular. The Hiver Federation and "Two Thousand Worlds (K'kree).
Meh, and lots of Foundation and Foundation and Empire deal with smaller polities and factions as well. Also, if you actually READ the stories you will quickly learn that, while the Galactic Empire is OLD it is not eternal and has ebbed and flowed over the millennia. Beyond that there was a LONG period before it became dominant. And yes, the scale of the Empires in Traveller is somewhat less, but the idea is still basically the same. If you look at Asimov's jump drive it has a much longer range, so a similar "limited by the speed of communication" empire is just physically larger. That doesn't really change the structure of the thing.
Traveller has no supersoldiers.
Classic Foundation (the Trilogy) doesn't have anything like supersoldiers. In fact its tech is VERY travelleresque with little in the way of discussion of personal communications and computing, etc. nothing about robots or AI, etc. etc. etc. LATER Asimov retroactively explained this stuff by invoking a tie-in to his other milieu, but that was quite obviously a revisionist move. The CT Empire/Universe and the Foundation Trilogy Universe are VERY similar in overall tone and form.
The Navies are age of sail, in core, and WW I in Bk5/Sup5/Adv5/Sup9, not WW II. Battleships dominate, not carriers.
The overall substance of the Traveller Imperium and its structure is an 'Age of Sail' analogy. Information flows at the speed of ships, which leads to a highly decentralized form of government with local officials and the possibility for things like character's reputations and crimes to be 'left behind', etc. Semi-independent planets, rogue bases, pirates, etc. can all easily exist within this framework. This is also largely true of the Foundation Empire, though it seemed a bit more centralized in some sense, at least it seemed clear that AT ITS HEIGHT the central authority was quite strong. OTOH the 5th Imperium is also pretty powerful, and Asimov outlines in the earlier stories how his empire has the classic 'General Problem' where military success on the perimeter results in competent leaders being recalled and executed because they begin to pose a threat to the center. Spinward Marches and related stuff indicates the 5th Imperium has a similar problem.
There is no dark age of lost tech. There is a dark age of no/very low trade, but that's not the same. Even the Ancients still, technically, exist at TL 22+...
Well, maybe in some later material, they're not a part of anything talked about in the earlier game, and even later the Ancients are merely some sort of remnant, or perhaps we could consider them some kind of "ascended beings" that don't really interact with us anymore. Note that Foundation, in its later material, basically does the same thing! The 'Robots of Dawn' are far more advanced than Humanity and basically run things! And again, if you read Foundation you will immediately find that there are indeed dark ages in Imperial history. Heck, they don't even know where Earth is! (that is later explained as one of the Robot's things, but in the original stories it is simply explained by the gradual loss of records over 10's of millennia of war, collapse and resurgence).
There's no established caste system; it's borrowed the Imperial Russian mode of increased social titles as rewards for service.
That was the common medieval system in every country originally, but I don't see any indication that you are correct here. According to the Traveller system you are born with a social status, and while it MIGHT increase or decrease slightly, there is no actual explanation of what might trigger that. I know of no particular way in which that is stated to differ from what exists in the Galactic Empire of the original Foundation trilogy. In any case, the exact mechanisms surrounding the choosing of an Emperor isn't some massive difference, and it is implied in the Trilogy that there have been many many imperial dynasties with different traditions and such over the vast history of the Galactic Empire.
You're seeing connections that simply don't exist to the strength you claim, overgeneralizing. Quite likely by lack of reference to the original breadth of inspirations. Hell, I've only read half the list of inspirations. I do recommend a read of Lensman...
I've read practically every single thing on that list at some point in my life, including every single thing ever written by EE Doc Smith. I agree, there are influences outside of JUST Asimov, but the Asimovian influence is by far the strongest. The instant I first read Traveller and ran a game back in 1977 I was quite aware of it, its hard to miss! However, I would say that Lensman, or Skylark either, are barely any influence on Traveller, with their much grander 'Wild West' kind of genre and super heroes sort of characters, ultra-advanced aliens, and Manichean moral system pervading the whole thing. The technology is entirely different as well, and I would classify Lensman as more Science Fantasy than anything else, though in tone it does try to 'feel' science-fictiony.
Marc's been very open about his sources. Dune's one I've not heard mentioned by Marc. (I have from one of the other GDW alumni.) It's possible he read the serialized version of Dune... but if he did, it didn't resonate with him the way the CoDo and Foundation settings did.
Yeah, I don't see a lot of the tone or feel of Dune in Traveller either. There's nothing like shield tech, or the whole highly intensely intrigue-based fighting, and certainly nothing like the religious aspects, or the secret societies and hidden plans being worked out over millennia. CoDo is a much better fit, though I would say that CoDo itself is pretty heavily influenced by Asimov! I mean, there was a kind of general Space Opera 'star empire' kind of pattern that a lot of stuff roughly followed back in the '50s and '60s particularly that is common between authors like Niven, Pournelle, Harrison, Asimov, Norton, etc. They all have some differences, some of which are fairly significant, but they all have a lot of the same elements too. Smith was of course the father of the idea of interstellar travel and civilizations and whatnot, so they all borrowed a bit from him, but Asimov put a lot more of a hard, humanistic, and science bent on it, and I think the others often riffed off of that more than off Smith directly.
My feeling is Traveller largely drew from Asimov, and then began to weave in some other stuff, like Norton-style Ancients and such. The original CT Universe is really surprisingly limited, much like the original Foundation Universe, with nothing but humans and the whole thing already colonized and filled with civilization. Its only later that we start to get into Aslan, and Hivers, and rumors of the Ancients (well, and adventures about them). Asimov obviously found his model too restrictive too, and we can easily see where Niven wanted things to be more interesting as well. It seems to me that a lot of the later material is more heavily indebted to other writers of the period. And then obviously you see some modest influence of more modern stuff with things like a malevolent AI and whatnot, which is definitely grabbing at some threads of Cyberpunk or related transhumanist stuff.
The CoDo influence is unmistakeable in Book 4: Mercenary, and explicit in Sup4's list. SgtMaj Calvin is from the CoDo verse. Early end thereof. Mote in God's Eye is the explicit inspiration for the black globe and white globe in Bk 5; it's the later end of the CoDo verse. (but if one wasn't aware of the conjunction, the Motie end (late end) of the CoDo can look very different from the Falconberg end (early end). The middle wasn't well developed.
Yeah, well, Asimov didn't do much really in terms of explicating military 'stuff' in his books. His focus was much more on society/politics/big ideas. Niven (and especially Pournelle) are well-known as some of the originators of the whole 'military sci fi' sub-genre. So, when Marc et al dug more into the military side of their milieu they naturally tapped the CoDo as a primary influence. Things like the 'black globe' didn't really seem terribly relevant, but I'm sure the idea is from Niven, or perhaps Arsen Darnay. It was certainly not intended to be something characters would run around with, but more like a plot device! In any case, I am not disagreeing that CoDo can be taken as a significant influence on Traveller, but I still think it is secondary to Foundation, and I think Foundation is a primary influence on CoDo itself! Note how Traveller's hyper jump system is lifted directly from Foundation, not from the 'jump point' concept of CoDo, although the range of the Traveller jump drive does fit better with CoDo. Nothing is ever going to be completely pure, if Marc had wanted to simply set his stuff in the Galactic Empire, he would have! So, clearly there's some diversity of influences.