RE: TT Decathlon as a "Second Plane"?
Welcome back...
With the way you have described your skills I woulld say have at it.
Flying a CUB is great for scale but rudder coordination is an absolute must with it which I am sure you already know. The Decathalon with be similair so you should have no problem.
Do you hate disorientation, sorry to hear about the "OOPPSS" with the VMAR.