* Loghain's plan was mot limited by Cailan; only where the King was to be during the battle was in play. And while others bear responsibility, The King and Duncan are dead, Uldred became possessed, and have no idea of that specific leader of the Chantry, but she was more instrumental in watching over the Mages while there. Only Loghain lived; how fortuitous....
Yes, he was limited by Cailan. Cailan wanted "a battle the bards would sing of for centuries that would end the Blight", which when you get down to it.... using Ostagar as it was meant to be used (as a garrisoned fortress where the soldiers aren't on the outside) isn't particularly glamorous, even when you're going up against a Zerg Rush from a bunch of tainted dipshits.
Cailan wants a glorious battle, but he doesn't want to do the leg work. He blows off the strategy meetings, yet wants something where he can "ride with the fabled Grey Wardens against a tainted god" in the field of battle. Loghain has to work with an idiot manchild's vanity and gloryhounding persona because any strategy that would be better isn't going to be good enough for Cailan. So using what information he has to go off of at this point in time -- "the horde is going to be larger this battle, but still can be defeated" -- he creates the Anvil&Hammer strategy to flank the Darkspawn, so that it satisfies Cailan's damned ego and can work out.
The Grand Cleric of Ferelden shows up later. Fun fact: the Chantry came out in support of Loghain throughout his Regency, from start to finish.
And it seems like you're trying to say that Loghain is responsible for Uldred being a ****** (never mind Cailan and Duncan being dumbasses). Nah, doesn't fly.
* If one has a snake attached to them, better remove it before the poison spreads further.
That viper has many tails.
or do you think that simply removing Howe would remove the only player on the board in that aspect that shouldn't be antagonized? If so, that's honestly a naive sentiment (no offense Elhanan).
Howe has his forces that are loyal to him. Hell, his son Thomas fought in the Civil War. You think he'd just lay down and accept his father being imprisoned and hanged? He'd turn against Loghain and rally people like Bann Esmerelle who would fight against Loghain on a third front, removing not only forces Loghain needs but also supply routes (the Pilgrim's Path runs from Denerim to Amaranthine and is critical for trade).
Howe is a snake and a slimeball but alienating him now when the entire Bannorn is deciding politics are better then putting aside emotions and facing the critical threat (the Darkspawn) is stupid.
* Poisoning Eamon via Blood Mage cannot be justified, to me at least.
Seems little different from the political games that are played all the time. It happens in Orzammar, Ferelden, Kirkwall, Orlais, etc.
If you have an issue with one, you have an issue with them all.
* Eamon may have been delayed due to poison, as Cousland was delayed due to treachery; uncertain.
Except Bryce sent the majority of his forces down with Fergus, while he stayed behind and planned to ride out with Howe's forces.
Teagan seems like a capable Commander; a bit of a fool when it comes to woman, esp those with Orlesian accents.
Ah yes, Teagan, the man who wasn't at Ostagar and rarely attends court, yet believes Loghain to be responsible for his nephew's death. The man who openly agitates a strained political situation at the worst possible time. This man is sure to be a capable commander who would be loyal to Loghain and not a threat at all.
Common lore is that it does take a Warden to kill an Archdemon
Common lore is that a Warden has always struck the killing blow, which is a different thing altogether.
A Warden being the one who killed the Archdemon doesn't in and of itself say they are absolutely needed. At best, it says that they know something that regular soldiers don't know
Even if Loghain believed Alistair betrayed him
Alistair was raised by a Fereldan traditionalist/nationalist who married an Orlesian noblewoman, then joined not one but two orders that trace their history back to Orlais. That second order was noted to have been collaborating with an Orlesian mage previously, rose up against the kingdom 200 years prior (justified though it was, no one knew the truth), and historically helped Orlais.
Given all that (and there's more to it, IIRC) it's not out of hand to suspect that Alistair is being used to satisfy Fereldan sentiments while giving Orlais an easy way in.