I'm afraid I don't know of any good receivers that have all the features you want for your desired $400 price tag.
For brand new models, the Marantz SR5007 would likely be the best choice, but its price is up around $850.
Accessories4less doesn't have any SR5007 refurbished units yet because it's such a new model.
And BoredSys already pointed out the other two best options out there. The Onkyo TX-NR709 at $450 from A4L is, by a fair margin, the least expensive receiver that includes a full set of pre-outs. It doesn't have AirPlay, but you could add a dock or an AppleTV, and the combined price would still be well less than either the new SR5007 or the A4L refurbished SR6006.
I'm certainly a fan of always having pre-outs available should I ever have a need or desire for them. Just isn't really possible to get them AND AirPlay for $400. Afraid you'll either need to increase your budget or look for a used unit from a private sale
