When I had an injury, to make things more comfortable I got a good Lazyboy recliner and made a simple lap tray (just a veneered board) to hold mouse, keyboard and remotes. Has worked out great! Recliner arm/lap board just needs additional 1" high or so leveling up front so mouse doesn't slide around or off (I just use folded cotton material for now).
Have Klipsch RF-7 towers, custom 15" Tempest subwoofer and Odyssey Audio 150 wpc amp & preamp along with additional Oppo BluRay/high-end audio player. My PC is behind the 42" HDTV.
I got a HP Pavilion Elite top-of-line a few years back with 9 gigs RAM, GTX 260 decent video card that has held up well after a ton of use. Wireless keyboard & mouse are Logitech MK700/710 & M705.
Anyone else here have similar or ergonomic setups?
To be honest I used to have a very similar setup to you in the beginning of my HTPC use. There is nothing wrong with it but in my experience there are much more comfortable and better options. I had a similar setup and then upgraded to a lenovo remote:
It worked ok but I was not loving it, the keys were harder to type than a standard keyboard. I saw a logitech k400 keyboard/mouse on sale for $5 so I jumped on it just because it was $5 not expecting much. This keyboard has been perfect for me, its relatively small but not as small as the lenovo (a good thing).