If you're creating a backstory for your character, you can easily just ignore the "you were crossing into Skyrim" part. Why? Because what you're doing has absolutely no actual impact on the game...you're simply making up reasons for your actions. You can still do that and just ignore whatever the game says...

Then its a case of mistaken identity and they think youre someone else.
I dont see the problem really.

No your character is just caught at the border. Why you were at the border and why you were caught is up to you.
The illegal immigrant stuff is a lie.

I can see where you're coming from, it's part of the reason I use alternate start mods for the Oblivion MQ. Prison works perfect for an evil character's backstory, but is harder for a law-abiding neutral or a good character's backstory.

Just remember, Tamriel is set in a middle ages and further back time period, so justice is harsher and less fair. You wouldn't have to necessarily commit an evil act to land yourself in prison in Tamriel. A good character may have tried to report a case of corruption, but the party involved had more influence, pissed off a powerful nobleman or government official, been accused of a crime due to race, tried to confront an evil individual who also happened to have paid off the local guard, etc.

A prison or execution starting point may be hard to justify for your hero, but that just means you'll have to work a bit harder on your backstory and thinknabout how your character's personality or circumstances may have gotten him into trouble with powerful folk.

To be honest, I'm not a fan of this illegal immigration malarchy. It seems to me that the Nords would just deliver some quiant in your face racism until the elves they don't like have left. They just don't seem the type to actually care about people coming to thier homeland, unless they don't like thier race. And even then, none of the races seem to be official enough to care about an immigration system.

I like the prison/execution start. It's traditional, and frankly, I think it gives more leeway in designing your character's backstory than if you just started out in a specific town for no particular reason. It raises questions like, "why this town?" whereas with imprisonment you can either milk it all you want or simply say your character was framed and start anew.

I personally couldn't care less if the execution thing was never brought up in the plot of the game. We should have full control over our characters' background, and aside from the whole Dovahkiin thing there isn't exactly any other objective excuse for people trying to kill you. So let's just leave it as vague as it was in past games.

Hopefully, when Esbern rescues you it won't be even more sudden a jump into the main quest than Oblivion's dungeon was. I'd rather he not swing onto the execution platform Robin Hood-style and escape with you out into the wilderness with guards and dragons everywhere, and then him telling you he's rescued you because you're the Dovahkiin or he "has a feeling" you're part of a prophecy or some nonsense. Total garbage. Being a Blades member, I'd much rather he pull some strings with the law and your character is simply released and thrown out onto the street, with you having no idea what to do next. He wouldn't contact you again until much later. Daggerfall-style!

Maybe you were caught trying to escape Skyrim because everything is going to Oblivion, and the other provinces have closed their borders to Skyrim trying to keep the frenzy from spreading. You get caught and handed over to Skyrim authorities. There, backstory fixed for all of you goody two-shoes.

And oddly enough then we would be back where we where when I started RPing and the referee wrote the adventure themselves.

No we wouldn't...we'd be at a stage where the referee had to do whatever the players demanded, because to do otherwise "restricts their roleplayzz!!one!!!"

True. I suppose you could say in a videogame the developers are the referee and my 1st rule as a referee was the referees decision is final
Happily for those of us on PC there are mods if we absolutely hate an aspect of the game.

Because that's their life?