Well that's impressive. You've heard the phrase: you can't have too many guns; also applies to desk space.
You know I am a big fan of dual monitors, I believe they offer much greater flexibility than a single, regardless of how big it is. By way of example, my right side monitor is my primary. The left side monitor always has T-bird open and Firefox open with a couple of tabs working. On the right, Chrome is open and is used primarily for online activity, surfing, research etc. At the moment, I am typing here on my right monitor, but on the left is Market Watch, a live bear cam I follow and a banking tab. I think a single screen would look cluttered.
I am really glad you're considering IPS panels, that technology makes a noticeable difference in viewing quality. You should also ensure whatever you select has a forward tilt ability as well as height adjustments.
Planning on a dedicated amp, allows you to use regular AV speakers, not typical computer speakers. You might want to consider a small sub-woofer under the desk. In terms of the hutch, I'd lose the two shelves under the designated speaker compartments. The area you set aside for the speakers is not tall enough, IMO. And you should allow space to angle them toward your chair Bookcase speakers using regular speaker wire will also solve the "short wire" problem. The pair of Creative speakers I have barely have enough wire between them to allow a left/right placement.
I am assuming you are going to eliminate the keyboard drawer in this process and put the keyboard on top of the desk. When I was designing my own desk, I discovered that the typical office desk is 30" high. The optimal typing height is 28". I'd consider cutting the legs on your desk to achieve the 28" height. It might feel awkward at first but becomes very natural quickly.
But so far, looks great.
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