A correction to an obvious mistake I made:
"Take off with full negative flaps works well" should read "Take off roll started with with negative flaps works well to keep the wings level".
One obviously needs to move flaps to neutral or +4 once there is enough aileron control. The tail won't lift off the ground with full negative flaps even at around 50km/h (31MPH).

I agree with the comments about tail wind take offs. I have seen and experienced what even a light tailwind of around 5km/h (3MPH) can do with regards to aileron authority and length of takeoff roll even in benign handling gliders such as Twin Astirs. Preferably don't do it unless the runway dictates it such as "one-way-in one-way-out" airfields or steep runways (land uphill take off downhill). It's definitely not on my TODO list in a Nimbus 2.