I've been playing a lot of Skyrim recently; as a result I've been thinking a lot about the lore. I've come up with some ideas on the future of Tamriel.
The Empire Wins the Civil War V1:
Ulfric Stormcloak is dead and the rebellion crushed. The empire is still however in a state of unrest: as every guild questline is considered cannon (if it wasn't the dragonborn that completed them then someone else) The emperor Titus Mede has been assassinated by the dark brotherhood and as a result the empire is ruled by the elder council. But of all places still under the empire's control the capital province of cyrodiil is the most unstable. Many already hated the the last emperor for his humiliating defeat at the hands of the Aldmeri Dominion. Will the emperor dead and his dynasty along with it the elder council rule as I said. We can already assume the council is pretty damn corrupt as the man who ordered the hit o Titus was a council member. The terrible unrest in the capital could possibly lead to a civil war. A new great war begins as the Dominion invades and conquers cyrodiil (which isn't hard due to the unrest, even if there isn't an uprising or civil war in the province).
What's left of the empire retreats to both Skyrim and High Rock. Since Skyrim has some many angry and strong nords who like to stick swords inside of elves it isn't hard to imagine them being able to hold off any invasion attempts, least for a time; especially with the Bretons of high rock's magic.
This leaves Argonia in a weird position. Now remember that before the events of Skyrim the Argonians invaded and conquered the Dark elf lands of Morrowind. With that they have a couple choices: They too ally with the empire and hammerfell, or stay independent. Both have issues. If Argonia allies with the empire.. well they shouldn't expect a lot of help, at least in the form of troops. Since their friends are on the other side of Tamriel, they can only give them supplies. Argonia would basically be alone against the Aldmeri Dominion. Now while the argonians are masters of gorilla warfare, they suffer on most other accounts. The only reason they were able to win Morrowind was the eruption of red mountain. That had dramatically weakened the dark elves, a large percentage of their population had migrated to skyrim as a result. So I doubt they could really stand much against The dominion in... anything other than gorilla warfare.
It is also possible the High elves could offer the dark elves freedom, letting them have their country back if they help them fight the argonians. If Argonia stays away from an alliance they could still find themselves in a war, that or they might even ally with the dominion at the promise that they would be left alone, we can debate whether or not they would keep that promise, same with the dark elves.
I will gladly post more of my thoughts later, such as a V2 of the empire winning the skyrim civil war and a theory and what if they lose.I would love to know what you think so far!