I wonder if gamesas is reading their forums? Anyhow this would be a great addition to stormcloak related quests.

So here's my idea.

For stormcloak you are given a mission from Galmar to investigate solitude, and to find Roggvir and save him from being executed. Theirs 2 spots where you can save him depending on the time of the day you enter solitude.

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  In the dungeon cell. (If you go to solitude in the night time hours) If you joined the stormcloak you will automatically get a trespassing bounty over your head once you enter the dungeon so you will have to fight off a bunch of guards and jailers. Once you do that you can loot a jailer's body to snatch the key that will soon release Roggvir from his cell. Once Roggvir is released he will thank you for freeing him, and start talking about how they didn't give him a fair trial, and all of that stuffs. You must guide him to where they stash the inmates belongings, and evidence so he can put on his armor (obviously his solitude guard uniform) and wield his weapon to help fight with you as you soon leave the dungeon and escape solitude with Roggvir.
  
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  Out in the execution block. (during the day) Theirs a group of 5 imperial soldiers idling near the entrance gate to prevent anything from interrupting the execution. You must fight them prior to entering solitude gates. Then you must find a solution to save Roggvir from being executed without harming the citizens. Once you untie Roggvir He will grab a nearby weapon to help fight with you.

To make things a bit more challenging Roggvir can die during the mission so you must be sharp, and watch his back. If he dies... well guess what? You failed the quest, and will get an ear full when you report back to Galmar. If he survives you are rewarded, and Roggvir joins in on rest of the stormcloak related quests.

Why must it be about fighting? That should only happen if you screw something up. I like the notion of infiltrating the dungeon to free him. It would be interesting especially if the player has some thievery background, either through the thieves guild or just self-motivated practice of stealth techniques. Go in wearing full Imperial armor. Get the guard on duty to "help" you with something and incapacitate him. Drag his unconscious form into Roggvir's cell. Roggvir takes his armor and both you and he leave together. As long as you are out of Solitude before the shift change, then the task can be completed without a single drop of blood being spilled. They won't know who you are. And they'll never see Roggvir again...

The player should have to avoid interaction with the legion and try to avoid being seen going to the dungeon. Too many people taking notice of someone new monkeying around where he ought not be could increase the risk of blowing his cover.

If cover is blown, then the option of fighting to get Roggvir out would be there. If prevented from escaping, Roggvir dies on the spot, and YOU get to be the one taken to the headsman's block the next morning.