Bondsmiths, assuming their surges are "Surface Tension" and Pressure, also would make powerful warriors, more of defensive ones, but still. I don't think it will be easy at all for him to give up his fighting life, I mean, he's been a warrior for a long time. Do you need a spren before you say the words, or is it the other way around, I can't remember? If it's the first, he couldn't become a KR on the Tower, he doesn't yet have a spren. I also don't think he's very pious. Somewhat, yes, but devout, I'm not so sure, I think he disagrees with some Vorin teachings.