Well I think I went too far.

Added the Super Skids - great, added a little stability to the heli.
Added the gy90 - great, gave much better tail authority
Added the microheli gear and main shaft replacement - great, less shaft bending on crashes and a cheap fix to buy just the main shaft
Added the dual tail - good and bad, better tail authority, longer motor life, but heavier overall weight - not too bad though
Added brushless main - good and bad, much more power and seemed smoother, but with more power there is less tail authority
Added the GWS DD Tail - my experience was not good. Too much wag, small push on props fly off (could be resolved with better tail rotor purchase as suggested)
Added separate esc for tail removing 3 in 1. Not much better on the tail control and a bit of an issue with arming the esc and shutting it down.
Added brushless tail and new esc - motor is very powerful (maybe too much so), even more drastic wag no matter the gain setting. Wonder if there is a way to drop the power output or regulate it better.

Maybe I will go back to the dual tail which seemed to be the smoothest of all. What a pain. Lots of crashes once I went past the dual tail with fly off props, too much wag and mysterious loss of tail power. Almost a crash per flight with some causing serious damage.

It is so close to being a great little heli for my back yard, but a major pain to constantly fix. The T-Rex is such an amazing heli to fly afterwards (yes I know it is in a completely different class), but my yard is too small to just yank it around like the Pro. Maybe I will fall back in love with the Pro when I go back to the dual tail, or if I can find a solution to the constant wag with the DD.