Killing his brother was simply a matter of honor and respect. He was the eldest and he carried the true claim. Renly owed it to him to fall in line like Stannis fell in line for Robert. Renly frankly got what he deserved. Stannis would have been more than fair to him if he had just bent the knee like he should have.
Davos already mentioned the Golden Company as the army they should hire. Stannis turned it down but he might change his mind. Stannis will have to bend his rigid ways if he wants to take the crown. If he knows a great battle is coming up north, he knows he will need a big army to fight it. Davos had a good point about willing to use black magic but not hire sellswords??
Stannis would make a great king. Nobody would dare F with him in charge. He would have Davos as his hand and that man is legit as they come.
You know Stannis is legit by the threat Tywin sees him as, both militarily and as a leader. Him being the Iron Throne would spell disaster for all the wannbe rulers. Except Dany, she is the wildcard to me.
Honor and respect over??? Oh over who was the rightful heir. I personally side with Renly on this one, as I think he would have made a fine king. He's likable, friendly, intelligent, and he had a much more impressive force than Stannis to command. There is absolutely no honor in killing your own blood over the right to a throne. So to say it had absolutely nothing to do with the throne is inherently incorrect.
And that's Stannis' problem. He's somewhat arrogant, stubborn, abrasive, and he often times makes brash decisions that end poorly. And Stannis would make a terrible king. Often times you want your king to appeal to your kingdom, because your citizens are far more likely to go along with you if you're charming, charismatic, kind, and and as shallow as it sounds, handsome. Stannis is none of those. He's cold, cunning, deceitful, unforgiving, and very fearsome. The kingdom would fear him and that makes for a horrible quality of life for the people within his kingdom.
Stannis has a fantastic mind for war and things the like but he would make a terrible ruler.
A quote by Roose Bolton that fits perfectly in this topic of conversation imo.
"You are mistaken. It is not good to be feared. No tales were ever told of me. Do you think I would be sitting here if it were otherwise? Your amusements are your own, I will not chide you on that count, but you must be more discreet. A peaceful land, a quiet people. That has always been my rule. Make it yours"
