Maybe, I haven't been keeping up with receivers enough to be able to confidently say I would get a certain one. There are usually quirks with a receiver, so I don't know what quirks (if any) the Pioneer units have and if they would be deal breakers for me.
The amount of money you're budgeting for the receiver is what seems quite reasonable to me. I've seen people that go out and get a $700 receiver and then pair it up with a 5.1 speaker set that cost ~$300. The bulk of your budget should be used on the speakers and subwoofer, which is exactly what you have planned.
Personally I know I like the rockets from AV123, so if I was making myself a system now I would be looking to see what "Santa Schifter" has in store
http://av123forum.com/showthread.php?t=38344 and see if that fit. Usually these end up being nice sale prices on 5.0 / 5.1 sets which might fit in well with your budget. Order fulfillment has been a read nightmare for some people over the last year or so over there though, so I'm not as confident in that recommendation as I was earlier. Since AV123 has deals on denon receivers, I would see if they had something competitive to bundle with it.
With a Denon, Onkyo, Pioneer, or whatever looked appealing, I would make sure to go on AVSforum and find the dedicated thread for whatever unit I was looking for. If there's any deal breakers associated with a particular model, that would be a great place to find it. I tend to research things quite a bit before I buy them, so I would want to thoroughly review all the options available before making that decision. Since I have not done that already, I'm not confident recommending something specific at this point.
Denon, Onkyo, and Pioneer have all been quite competitive in bringing some great features to receivers at this pricepoint though. I would certainly compare what was available at these three companies along with HK and Yamaha.