You get more power from Str than Int, but most of our dammage (and by proxy...some aggro) is spell based (Int reliant).
However crusaders start with the lowest Health pool of all fighter classes, and the highest Power pool of them.
I went with STA. Personal taste really...I wanted a meatshield SK from day 1, so I built mine to take hits. Every choice I had that could go STA, AGI, or WIS, +health pool % etc.. is what I went with. Has filled my needs perfectly. I pretty much use him exclusively for raid tanking...with occasional instance runs if guildies need a tank.
He can take an extreme beating...but his DPS is quite low for an SK. I compensated lower aggro from dammage with the EoF Hate line, decent INT gear, melee crits DOF STA line, and some EoF AAs in decay. Works very well.
Best to decide what role you want and spec accordingly (can always respec later though if you're not sure early on).
Happy hunting, and welcome to the SK community :)