Hello Rich...

Sorry to hear about the tail strike. Here's a suggestion:
Since you have already held the plane while the rotors spun up, how about doing it again and noting whether the plane wants to tilt one way or the other, whether it feels like it wants to fly out of your hand. While doing this, it is possible to adjust trim settings so that it feels as if it wants to fly straight and level, etc.

I would also agree with Phil that 20 degrees of side tilt is probably a lot more than needed. Also the tilt back probably should be reduced to around 5 degrees.

Judging from the photo you included before the flight, it appears that the rotor mast is plenty high. Adding more height, will simply add to the "pitch-up" tendency. Making adjustments to the tilt-back is easier.

The fact that you noticed the front of the rotor tipped up when you started to taxi fast suggests that the high tilt back put pressure on the blades at the front causing them to be "blown" upward. Which then suggests that the rotor really wasn't up to speed yet...not enough centrifugal foce to keep them in a flat plane.

Hope all these suggestions don't seem like "preaching". It's so much easier to armchair quarterback than actually be doing it! <G>

Anyway, it sounds as if you are pretty close to success. The plane sure looks good.

Bill