If you liked the Imperial missions you'll love the Stormcloak missions because they're exactly the same.

Haha, true.

This is actually sad but true, there goes originality out the window.

A Bosmer has "vengeance for my murdered kin, and retribution for not allowing them to become one with the forest in the way of our Ancestors"
Any Khajjit "They wish to limit our sweet Moon Sugar to control us, They will suffer the death of a thousand scratches for the idea"
An Argonian, "The Hist speaks to me, if I help the Snowmen now, I save many future generations of my cold blooded kin, the Dominion will target Blacmarsh last, but they can not do this if they are stopped before it happens"
EDIT for spelling and clarity

The Hist are a dangerous threat and the oldest being on Tamriel I am curious to see what would happen if somebody were to invade Black Marsh now thay would surely be a spectacle.

I can't ever justify my characters supporting the empire, they allow the thalmor to brutally slaughter worshippers of the god/man that actually founded the current empire!

Signing the WGC shows such weakness, lack of respect for the empires roots and disrespect to the innocent worshippers of the god that most of the empire secretly worship, yet they sit back and let the thalmor murder their own.

Yes some of the stormcloak are racially intolerant to members of altmer and dunmer, but over time after skyrims independence the racism will subside, Ulfric even says so himself when talking to Galmor, after the war putting such a strain on Ulfrics finances he be less strict on who he helps. Do remember why those mer are disliked in the first place, they weren't exactly good in the past.

Ulfric is also a strong figurehead for the people, so if the thalmor come knocking he and the dragonborn can lead the armies of skyrim against them, the thalmor have no power greater than the Thu'um.

I can't ever justify my character supporting the weak and disrespectful empire, the best thing for skyrim is independence.

I'm not sure what I'm about to say will help you, but there's one teeny, tiny reason I joined the Stormcloaks: the Imperials were about to chop my [bleeping] head off even though my name wasn't on the list! If it wasn't for a dragon, I'd be dead!

I made my mind up right then and there to hate any character wearing a red skirt.

Tullius has skinny legs and wears a skirt. I rest my case.

Choose the bigger one.

Politics are as good as any other reason. My first character, an Argonian, joined the Stormcloaks and while he didn't approve of some of their methods (mainly the racist ones) it would be quite the hypocrisy if he was willing to die to defend Argonia's independence but not Skyrim's. The Empire was more corrupt to him and the very thought of them lying in bed with the Thalmor made it worse. Knowing about the racism that flowed in Cyrodiil also shines bad light at the Empire, especially when they try to hide it from public knowledge. Not to mention that the Empire made it personal when they almost wrongfully executed him and later his lover, then murdered a very close friend, desecrating the body in the process.

Even more so since the last major event Argonia suffered was 160 years ago. The Great War was 30 years ago. IIRC elves aren't the most productive breeders and since Argonians have had more than a five times longer time span than the Thalmor to rebuild their military, the two factions have at the very least even military power.
Under Hist influence, the daedra were forced to close the Oblivion gates themselves because of the Argonians' ferocity. The elves didn't fare as well as the Argonians. So Argonians under Hist influence are quite the threat.
EDIT: And to my knowledge, no faction has ever truly conquered Argonia. Not even Tiber Septim or Reman II succeeded. The inner swamplands near Helstrom has always been Argonian.

This is what I did. I created a character who would be emotional about it. Hrafngoelir was a true Nord, and was truly ticked off when she came home and the first thing that happened was that the Empire tried to murder her. Then all this nonsense about banning the worship of Talos, Mighty Talos! The founder of the Third Empire. The dragonborn! Shor's Bones what madness is that? Even worse, the Thalmor stalk the land, dragging off true Nords to be tortured and murdered, all with the Empire's support. In her eyes, the Empire betrayed her, and Skyrim, and sold them out to the elves.

Even taking all of the emotion out of it, it is just a matter of creating a character who feels that A - people have the right to self-determination, or B - People have the right to choose who they will worship, or C - getting revenge on those Imperials who tried to kill you at the beginning of the game. Any one or all of those above are good motivations for a character to join the 'cloaks.

Now you know why I married Ulfric!

Unfortunately no. That was Decianus's decision and it was completely against the emperor's orders. Plus it was only a small contingent of his legion. Not legions.

I find that peoples opinions on Ulfric vary greatly depending on their opinions of the Nord race. And sometimes their IRL race.

Dunmer for life right here though. Ulfric can choke on a fireball.

One does not simply walk into Black Marsh.

What would happen? Another Knahaten Flu, infecting and killing everyone except the Argonians.
That epidemic wasn't a coincidence either. The Hist and the Argonians are bidding their time.

I'm not an Ulfric supporter at all, but the way i see the war is this; Do you want a province to retain its traditional herritage or do you want a single governing body that destroys the beliefs and traditions of each province invaded, making them fundimentaly equal (defeated)?

Do the quest in Whiterun about Thorald Gray-Mane being missing.

I don't know that he ordered it, but it certainly seems like he was complicit in letting in turn out that way.

Take it from a grizzled, weary old veteran Nord who sided with the Imperials, the Stormcloaks were right. The Empire is corrupt, it doesn't care about Skyrim it cares about power. Look at how it abandoned Hammerfell to the Aldmeri Dominion ? If the Redguards can beat them back alone so can the mighty Nords. The Stormcloaks may not be perfect, but neither is the Empire, Skyrim needs to be independent again, it needs to be strong, for too long it's svckled at the teet of the Imperials, for too long it's bled for them only to have their sacrifice thrown back in their faces when the Empire crumbled and gave in to the Dominion.

The Nord way of life is at risk, the Nord race is at risk, the Nords once struck fear into the hearts of every race in Tamriel, it's time they reclaimed their honour.

I think it is a personality thing. Some people like Imperials, others like Stormcloaks. All the logic in the world is not going to change anyones point of view. I am the opposite of you. I cannot stand Imperials. They seem like a bunch of petty bureaucrats to me. But I have an Imperial character so I can do the Imperial civil war quests. It's fun playing a character you consider to be a "jerk" sometimes. For me, that would be an Imperial. For you, that would be a Stormcloak.

If I can enjoy playing an Imperial, I am sure you can enjoy playing a Stormcloak. They get to swagger a lot and drink mead, and boast and shout and fight with a big Nord axe. What's not to like?

I have not finished the Stormcloak questline yet because I want to savor the moment when I can put that dog down.

That's one of those things that made me go Stormcloak on my first character. I was new to TES and the whole genre and just following the obvious prompts so I ended up in Whiterun right off, and it wasn't too hard to pick a side between the Battle-Borns and Grey-Manes after my first few interactions there and some of the things I witnessed.

I know you can't tar a whole faction by the actions of a few of its worst members, but some things are just hard to get over, you know? Seeing the Battle-Borns in such dismay is always the one thing that eases the lingering Stormcloak guilt of having attacked my "first home" in Skyrim and deposed Balgruuf... even though I am not as enamored of him now as I was at the start, I still think he's a cut above most of the other Jarls.

I know what you mean. Really wish Beth would have had Balgruff siding with the Stormcloaks. Although I thought the new jarl was too nice to the Battleborns by letting them stay in Whiterun. Those traitors should have been exiled after what they did to the young Gray-Mane.

Sounds painful.