Elantris is the least well written, so read it first or not first depending if you want to lose interest in Sanderson, or be let down by the writing style. The rest are excellent though.
I remember reading an reddit ama by him where he said his process of writing is more of an architect style: that is, he develops the overall arc of the major events in a series, and then fills in the details in each book. This allows him to project book release dates 1-2 yrs. out.
I enjoy Sanderson, but I really enjoy knowing when the next book in an enjoyable series is coming out as well.
Disclaimer- I'm a mere show-watcher, and avid reader of gameofthrones.wikia.com :-)