In term of skill upgrade, coaching is what you need.
For racket, its not upgrade or downgrade. Its more about how the racket could sync with your growth in term of stiffness & stability.
So, what do you want to achieve from expensive racket? What you find lack on your current racket?
If you just want new expensive toy, the obvious path are 88D Pro. The others would just be different racket which you might like or not coz its different characteristic, frame profile, & all.