Well, as BSparrow and Redsrock have mentioned, you have to do this tastefully. Technological advancement is a must, but it has to include magic, differing races (high elves live longer, this gives them an advantage), ayleids and dwemer, etc. Sit back and plan for a very long time, draw up the entire world. Have an idea what is happening everywhere to everyone and why, but be sure not to tell us all at once. Say it context; the thing I hate most with future Tes is people say things like "The Empire is fallen, High Rock is on the move, and the Dunmer have invaded Akavir"
I suggest doing it from first person, just to be different and exciting. First person can provide the kind of mystery that would make this kind of whole new world thing exciting. Normal fan fics can use third person because mystery is usually very low outside of characters. Just a suggestion though.
Also, don't be afraid to go even further in the future. I think you said it would be equivelant to 2250, so make sure you have really advanced tech WITH LOTS OF MAGICAL INFLUENCE. One thing you can try is big corporations in the form of the guilds. Everyone would turn into Hlaalu
Think about today, only add magic about three thousand years ago. It sounds hard, but you'll stumble on an idea and just go with it one day. Do NOT force your planning or inspiration.
Sounds promising, I look forward to it. Thanks, and keep it up :goodjob: