Don't worry, I doubt we'll get to see a TES game in Kirkbride's expanded universe. I think C0da might just be the point where his work and that of the writers at Bethesda split off.
It did inspire me to go back and reread some of the stuff hidden in the lore. For instance, the Thalmor banning the worship of Talos, while technically a new concept (and one people are glad to bring up when they try to defend the Stormcloaks), is just a continuation of things that were happening long before Man even walked on Nirn. As with everything TES, it all comes back to Lorkhan. Talos is nothing more than an aspect of Lorkhan, and he was much more than just Tiber Septim while mortal. Talos represents several beings, which all had a connection to Lorkhan. Lorkhan being, of course, the god who set in motion the creation of Nirn, and the eventual entrapment of the Et'Ada, which would lead to them becoming mortals. Lorkhan has always been the mortal's god, and when Auri-El ripped out his heart, speared it on an arrow and sent it flying across Tamriel, that just became more evident.
The Elves despise Lorkhan for their mortality. The ironic thing is this: there's no sign that Elves, even the Aldmer, were ever immortal. They were once spirits, true, but so was everything on Tamriel's surface. Some of those Et'Ada became the laws of nature. Others evolved into the mortal beings that now dwell Tamriel. In a way, the Thalmor should be supportive of Talos worship, since the beings he's comprised of were mortal, just as them, and proved that ascension was possible. And yet they cling to this belief that the worship of Talos (and, by extension, Lorkhan) has to be quelled.
Why? Lorkhan. Shezarr. Shor. Call him what you will. His heart, wherever it may be located now, is the beating heart of Nirn. It's one of the things, along with the towers, that keep the world anchored where it is. The Thalmor, obviously, want to unbind this, so they go back to a state of timelessness, formlessness, and, in effect, deathlessness. If you recall, the Crystal Tower on the Summerset Isle was destroyed during the Oblivion Crisis. It's said that the Daedra were responsible for that, but were they really? The Thalmor were already trying to advance their goals during that time, they were just a fringe political party. It wouldn't be completely insane to think that they'd want to topple the one thing on Alinor that represented everything they wanted to undo, would it?
And that's why they want worship of Talos banned, as well. Because of his connection to Lorkhan, the missing god. You can be damn sure the Thalmor will be actively searching for the Heart of Lorkhan as well, so I'm positive they have a presence on mainland Morrowind (and Vvardenfell) as well, as that is where the heart was last seen. They also almost managed to topple the White-Gold Tower in Cyrodiil, but were driven back during the Battle of the Red Ring. Levelling the tower, and the city with it, will definitely be up there on their 'to do'-list once they get back into full-scale war. It's why they wouldn't let go of Hammerfell, either: they probably wanted a base of operations close to the Direnni Tower in the Illiac Bay. And then there's the Throat of the World, though what their plans are with that remains to be seen.
What I'm trying to say is this: the Thalmor really are the greatest threat out there right now. Alduin has been vanquished, so the end of this kalpa has been indefinitely postponed. They've managed to trap the Imperials and the Nords in a stupid, useless war. Humans, beast races and dunmer are divided. The Empire is barely holding together, the Redguards are in an uneasy detente, the Stormcloaks are crying liberty (which, when you take the above into account, is just fucking stupid), the Dunmer and the Argonians have ripped themselves from the yoke of the Empire and gone to war as well: it's no wonder the Thalmor have gotten as powerful as they did.
I see people who want to know the resolution of the civil war in Skyrim. They probably never will. By the time the next game is set, whatever choice you made will be rendered irrelevant in the grand scheme of things. The Emperor's death is probably the most important thing in that game, lore-wise. I'm guessing it'll be the death blow for the Empire, finally splintering and leaving only war and turmoil in its wake. But, maybe the races of Tamriel will wisen up and remember the threat they've got eying them in the west. Maybe.
Tl;dr: Thalmor real bad, yo.
