Thank you for your work!

I think you did a great job!
What I miss is a variable to control the system/GPU load.
The --interactive flag does not really work for me, I even experienced greater desktop lags with "interactive 1"...
For interactive you need to let autotune choose a smaller workload. Manually specifying the same -l parameter as for non-interactive mode won't be a good idea.
Interactive mode will be trying that you have around 60 individual CUDA kernel launches per second, and a millisecond of CPU+GPU sleep time inbetween. -> 60 frame updates on the display should be possible, so you can watch movies or porn or whatever while mining

Christian