That sounds like a nice PC that should be plenty powerful. I have done a bit of research but haven't built a system yet. With that caveat in mind, if it was me and providing the computer had the slots, and budget permitting, I would be looking at:
- a dual or quad terrestrial tuner card (Amazon UK had a better range than Amazon US last time I looked)
- possibly a dual satellite tuner as well
- possibly a Hauppauge colossus if you wanted to capture HDMI output from Sky/Blu Ray etc at a future date
- a second hard drive in the 4-6TB range, or a multi-bay NAS on the network
- NextPVR (or Myth TV)
- MCE Buddy
- Plex
Then I would network it. I think you can set up automatic processing so that once a recording is done MCE will strip out the commercials, then flip the finished file to Plex for indexing and viewing. Cheap clients, such as Kodi on Raspberry Pi, could then allow for viewing of content in the main room, and across a network in the bedroom etc.
EDIT: Typo