I've been standing since 2007 and I love it. An external monitor and keyboard setup is important for me, since the laptop keyboard and monitor are too close together to be able to both type comfortably and see the screen with my neck in a good position, but that might just be because I am very tall and have a long torso.
I have arrived at a very interesting angle for my keyboard which I haven't seen elsewhere. I use the Kinesis Advantage and built a little wedge out of wood to stand it on so that the keyboard is pitched in the opposite direction than most. It is arranged to be much higher at the front than the back, almost vertical, so I can type without bending my wrists or elbows at all. Can't see the key caps in this arrangement but I can touch type with my eyes closed.
I also have a huge external touchscreen monitor designed for windows 8 that I managed to get working on the mac. It's much nicer to use than a mouse or a trackpad although making extremely precise mouse movements is hard and I keep a regular mouse around to use when needed.
>I use the Kinesis Advantage and built a little wedge out of wood to stand it on so that the keyboard is pitched in the opposite direction than most.
MS Natural started doing "reverse tilt" since the first version and still going strong with it.
I use Kinesis Advantage too and had to build stand from cardboard and scotch tape to add reverse tilt - otherwise I get wrist pain. It boggles my mind that $300+ keyboard doesn't have this basic feature built-in (and don't even start me on split, why, why they removed splitted version with optional touchpad?).
I have the same keyboard (with a Kinesis keyboard tray) and while it's not as sloped as yours, I'm maxed out on negative angle (while sitting).
The most important thing is that the keyboard height and slope match so your wrists are straight. In general, I prefer having my elbows more open because I find that minimizes arm fatigue, but having the elbows open would definitely not be a plus if it forced your wrists into extension.
The reason I arrived at the setup I have is because I got RSI and first switched to a standing desk where my elbows were bent, which caused even more pain. I was forced to try different positions until I arrived at the one that I use now, in which I tried to keep my joints in as neutral a position as possible.
I have arrived at a very interesting angle for my keyboard which I haven't seen elsewhere. I use the Kinesis Advantage and built a little wedge out of wood to stand it on so that the keyboard is pitched in the opposite direction than most. It is arranged to be much higher at the front than the back, almost vertical, so I can type without bending my wrists or elbows at all. Can't see the key caps in this arrangement but I can touch type with my eyes closed.
I also have a huge external touchscreen monitor designed for windows 8 that I managed to get working on the mac. It's much nicer to use than a mouse or a trackpad although making extremely precise mouse movements is hard and I keep a regular mouse around to use when needed.