Honestly, unless you are wanting to blow down your walls, I don't see why you need separates. The reason is that your Definitive speakers are pretty efficient, at 91 to 92dB. Plus, each of your BP 7004, as well as your 2300, has its own sub built in, so your receiver is not taxed with driving the deep bass.
For what it's worth, IMO, I think you will be very pleased with the results you get with an Onkyo 809 receiver, which also has a phono input. I have the 809, and contrary to the popular notion that all receivers sound pretty much the same, I found that the 809 sounds noticeably better, on both music and movies, than the Yamaha RX-V1800 it replaced. The 809 has much better decoders and internal amps than your 605. Plus, there are some deals available now on the 809 around $500 to $600. You could always add separate amps later, if you felt compelled.
For what it's worth, IMO, I think you will be very pleased with the results you get with an Onkyo 809 receiver, which also has a phono input. I have the 809, and contrary to the popular notion that all receivers sound pretty much the same, I found that the 809 sounds noticeably better, on both music and movies, than the Yamaha RX-V1800 it replaced. The 809 has much better decoders and internal amps than your 605. Plus, there are some deals available now on the 809 around $500 to $600. You could always add separate amps later, if you felt compelled.