Kevin,
One other thought. Before you go down the 2-channel only path and all the compromises that entails when trying to do an HT sytem as well as a 2-channel system, try to listen to a good SACD and DVD Audio 5.1 music system on a good HT system.
You just might find that you prefer 5.1 music to 2-channel music then you can set-up your HT system and with the flip of a switch you can kill two birds with the same stone, so to speak.
Oh and by the way, you can always listen to 2 channel only music on a 5.1 system but a dedicated 2-channel system has a really hard time doing discrete 5.1 channels.
Basicaly with your Onyko as your pre and a $2000 dollar Sunfire 5400 as your 5 channel amp and a new $499 Oppo BDP83 as your universal player, you could have the beginnings of a nice little system that would be a good start along the upgrade path. It would work today and certainly be good enough to blow your family and friends away and then you could upgrade each separate component, pre, Universal Player, DAC, etc. as time and money permits.
I personnally started this way and still have a dedicated HT with a Sony ES5400 as a pre and a Sunfire 7400 as the power amp with 7.1 channels of Logans all around. It is a really nice system that does play music now and then, but the nice thing is that I can enjoy the HT now and I could always upgrade different components and over time I have and I will continue to do so, with a focus on HT stuff.
I am lucky enough to have a dedicated 5.1 music only system and although it has a monitor to control my 5.1 music sources I do not use it for HT, just music and I never listen to two channel on either system anymore, but that is just me, YMMV. I got hooked on MCH and have never been able to listen to 2 channel since.
Many here are diehard 2 channel fans and that is okay too, I understand that. But until you sit down and (experience):rocker: good 5.1 surround sound music you don't know what channels you are missing, so to speak.
Good surround sound is a listening experience, it tends to go thru you, sometimes it gives you an almost out of body experience, and it can wear you out, it is definitely not for everybody.
The point is, try it. Experience it for your self, it may make all your future decisions easier and somewhat less complicated....or maybe not.