I personally disagree. Most people are encouraged to read Brandon's books in the general publication order because that's the way Brandon had intended them to be read. They are, for the most part, linear. Secondly, they are actually more user-friendly, for lack of better term, to be read that way. Whilst I love the Stormlight Archive, I don't think I would have gotten into it as I did if I wasn't already familiar with Brandon's works like Elantris, Warbreaker and Mistborn. For me SA was the natural accumulation of the knowledge and skill from his previous books.
Plus each book is supposed to give you a little bit more information on the Cosmere as you go. Why would you want to spoil the surprise? One of the best feeling I got from these books was the dawning realisation that something was going on, some link was happening behind the scenes; this bigger picture. I could read each book and enjoy them for what they were, whilst at the same time the Stormlight Archive is slowly painting those things I learned and noticed in Brandon's first publications into a bigger picture. All this before the last Mistorn trilogy!
Honestly, If I read SA first I would probably find all this secret behind-the-scenes Cosmere stuff to be jarring. SA is complicated enough with intrigue and secret groups like the Diagram, Sons of Honor, Skybreakers etc without Hoid and the Cosmere adding its own drama to the mix.
In conclusion: If you are reading his books for the first time, don't read them in a particular order for the sake of figuring out the Cosmere (good luck!), but for the single enjoyment of each book/series. I guess if that's a different order than standard that's okay. I didn't read them exactly in standard order either.
If it's not your first time reading them.... do whatever... GO NUTS!