Be aware about the UMC-200 and the upgrade card, the XMC's price has gone up twice and it hasn't even been released yet. Currently they are projecting it will come in at $2000 minus the discount with the upgrade card, just FYI.
For the Oppo 105, since you have 4 sources and it only has 2 inputs, it wouldn't work so well without a work-around like an HDMI switcher, and you might as well buy something that meets your needs without adding complications.
For the 2000 price range, Marantz really is the best option for a pre amp processor. They do seem to have a bit of a price premium, however. One other option would be an AVR used as a pre amp only. The Denon AVR X4000 is very flexible and has the TOTL Audyssey room correction for 1400, but I've heard of people getting solid discounts on it.
For the Oppo 105, since you have 4 sources and it only has 2 inputs, it wouldn't work so well without a work-around like an HDMI switcher, and you might as well buy something that meets your needs without adding complications.
For the 2000 price range, Marantz really is the best option for a pre amp processor. They do seem to have a bit of a price premium, however. One other option would be an AVR used as a pre amp only. The Denon AVR X4000 is very flexible and has the TOTL Audyssey room correction for 1400, but I've heard of people getting solid discounts on it.