I agree completely. I can see why Blizzard would place him at the top, seeing as Stormwind is really the most active member of the Alliance in terms of anti-Horde movement, and also arguably the strongest member of the Alliance (the Night Elves and Draenei are a bit preoccupied with their own efforts to be considered really "strong"). But given Wrynn's horrible decisions which seem to conflict with the Bronzebeards as you said, and his severe reaction to the Wrath Gate (which visibly disturbed Jaina) I'm surprised he is able to hold such command over Ironforge and Theramore, much less the very disconnected Darnassus and Exodar.

While some NPCs (namely Jaina) disagree with Varian's reaction to the Wrathgate, I think Blizzard is trying to show us that a large part of the Alliance is fed up with the Horde, those present at the Wrathgate, veterans from the first two wars (some are seen wandering Stormwind), those who lost loved ones to the Horde off-shots (namely Forsaken, and Shadow Council), probably think it was about time someone took an hard line with the Horde.

As for Magni, well he was always a bit of an isolationnist, he wanted to shut off Ironforge to prevent dwarven involvement and he's never been shown as extremely insterested in Brann's adventures, and he still holds a grudge against the Lich King. So when Varian said the Alliance would concentrate on Icecrown instead of Ulduar, he probably agreed.

Personally, I suspect that the return of Wrynn and his sort of self-appointed leadership of the Alliance is probably more calculated on Blizzard's part than it currently seems. Not only does it serve the immediate purpose of increasing the tensions between the Alliance and the Horde, something Blizzard has said they were planning on escalating, it also sets up a whole lot of possibility for more in-fighting and drama amongst the Alliance down the road.

What if King Wrynn makes a unilateral decision so unpopular that it threatens Stormwind's relations with the rest of the Alliance? (no real-life parallel intended...) That could lead into some very interesting plot lines in further patches/expansions. I can't imagine the Alliance will fall apart or even lose any of its races during WoW's lifetime, but I can certainly imagine that the threat could arise and would create a richer storyline than a simple Alliance vs Horde or Alliance&Horde vs _____(insert enemy here) storyline.

IIRC back in the days of vanilla wow none of the alliance nations had a strong leadership at all.

Humans had lost their king

Magni was innefective and consumed with grief facing the "death" of magni and the fact that Brann may have met a similar fate as well

Gnomes lost their city

Night Elves were nearly at a civil war between the hardline and xenophobic faction (led by fandral staghelm) and the more open resigned to their fate faction led by tyrande

Now BC pretty much took care of the humans and the night elves (giving them a purpose and an ally) but all the sudden Magni is better and no longer looking to help his brother? In all honesty Blizzard probably just forgot about him.

Also IIRC the Dwarves not the Humans are the strongest and most numerous amongst the current Alliance, which is why Ironforge was the original "capital" city the counterpart to Orgrimmar (back then only org and IF had auction houses) and why the Dwarves not the Humans are fighting in Alterac Valley.

I'm a little confused too. When Bolvar was taking Varian's place, I always assumed Jaina was the leader of the Alliance.

Everything you EVER wanted to know about Varian - and why he's so dang ticked off. http://greyshades.wordpress.com/2009/11/17/character-focus-king-varian-wrynn/

Long article, but I covered -everything- I could find on the cranky little bugger.

Even if Varian isn't the "official" leader of the Alliance, he remains the de facto leader simply because as the king of Stormwind, the most powerful nation currently on Azeroth, in addition to the commander of the Alliances military, he holds the most clout in the Alliance.

Pretty much every other member of the Alliance would fall, except possibly Ironforge, if they got on Stormwind's bad side.

On a more practical note, it's because the Alliance had no clear leader to rally behind since Terenas bit it in WC3. The Horde had Thrall, who's arguable a "big green Jesus" to rally behind, while the Alliance had nobody. This leads to an immense amount of Horde pride and next to zero Alliance pride.

Varian's job was to rally the Alliance, and muster up some Alliance pride, and I think he's done a great job of that so far. At Blizzcon this year, I think it was the first Blizzcon I'd seen where the Alliance was showing Alliance pride, and responding to Horde cheers with their own.

All hail King Wrynn!