I'll be curious to see your results.
http://jacob.j-e-b.net/nicehash.odsThis was taken using a 1 minute counter and a 1% averaging. No compensation for ramp up/ramp down (integrated solution would have that) and no hashrate recovery.
The lower two are X11 and X13 on "nicehash control", the upper two are scrypt and sha256 on "p=xx", with the initial hashrate for scrypt misconfigured.
Looks good to me (looks better when the graph is not that compressed), more after work...
How does this compare to the numbers coming out of the miner? If the red line is close to what the miner reports then you really have something here.