Yes the high QB ACC for CPU was done to increase short open passes, I'm slowly creeping down the CPU catching to help keep their numbers down, if you don't have a good pass rush and a suspect secondary, you will get picked apart in real life, so I don't want to take that away, but I'm still fine tuning to get stats realistic but the gameplay is pretty solid.
In regards to the d lineman running one back, it has happened in the NFL plenty, also a lot of d lineman have good speed in the game as far as their ratings, but I don't see this type of stuff too often, but feel free to tweak as you please, I'll be making some very minor tweaks over the next couple days, specifically to CPU catching, HUM QB ACC, HUM pass block, and HUM/CPU run block.
I really like the run game, if you stick with the run you'll be rewarded, but there are those runs that get stuffed or have minimal gains and I like to see that.