Replying to BMCC vs. GH3 vs. Canon 5d Mkii

Guys I know this sounds extremely dumb and I'm sorry I had to reach out to you, but I need some feedback on a decision I'm trying to play out in my mind. I currently have a 5d mkii with a tamron 24-70 f/2.8 lens and a couple primes. Historically I've shot a lot of photos but lately I just shoot a lot of video (probably for the last 18 months or so.) Anyway I've had this nagging going on inside of me wanting to switch to a BMCC or even a gh3. Does it sound completely stupid to scrap a perfectly good system for something else? Is the change really worth my effort? This is meant to be an open discussion about how everyone feels about each individual camera and basically I just want to hear everyone's (specifically those who own one of these) pro/con lists of each. Thanks!