It mainly boils down to whether you prefer actual buttons, or touchscreen. I strongly prefer actual buttons because you can feel for the right button in the dark, and not have to look away from the TV to find the button, or use the backlight.

On the other hand, an LCD touchscreen means the button labels can change a bit, and will be a little closer to their actual function whereas on the SL9000 they won't be close at all (unless you use the stick-on labels). But the Sony's LCD is only semi-customizable, you have to pick one of the labels they chose for a button.

What do you have against Marantz? The RC2000 Mark II is a lot more powerful since you can choose your own 4-letter label. I'd recommend that over the Sony, though it's more expensive. I'd also recommend the Marantz over the SL9000 if remembering the location of functions is going to be difficult for your wife.