Your DX6 is commonly used for helis like the T-Rex.
A sim will go a LONG way in reducing costly crashes, and it will also be used when you want to try more advanced moves. Every pilot I know who does more than hover owns a sim and uses it a lot. Every one. Realflight G3.5 and Reflex are popular.
If you have already seen and do not like iffy tail control, I would say that a T-Rex 450 with a GY401 is what you need.
Vince