Making headway. I'm posting here incessantly because this was supposed to be my weekend project so this is what I'm doing instead. Ha. I keep telling myself it's funny...
I found out if I record arm ANYTHING then CPU usage jumps up to 100% (30% in Windows). Definitely a software issue and definitely inside of Pro Tools. If I remove (not bypass) Ozone on the master it only goes up to 40%. Further if I disable QL spaces on the reverb auxes it only goes up to 15%. The fun part is if I remove all virtual instruments and leave Ozone, etc., CPU usage does not change at all when record arming. This is only if I remove ALL of them - it's not tied to a single manufacturer. I tried systematically removing each from the plugins folder and trashing prefs in between with no luck. This is a huge problem as I need them record armed and playing back live during recording, meaning an overhead of 40% CPU usage.
I found a workaround and possible explanation here:
http://duc.avid.com/showthread.php?t=380961
By setting my processor affinity on Pro Tools to ignore core 1 entirely (second core and it's accompanying thread) and setting my buffer to a whopping 2048ms (it's all sequenced so actually no big deal), then I can get the project to hang out just under 100% CPU load in Pro Tools when record armed and playing back input. This is completely ridiculous. It still hammers that core for whatever reason, but telling it to not process on the ones it seems to like spreads the load more evenly everywhere else.
Absolutely silly resource management. I'm going to test with another DAW tomorrow and see how it compares.