In my opinion of the skill level chart
beginner-doesn't know basic theory,only knows the notes on the keyboard, can only play songs they practiced at home,can't hold down a service
intermediate-can play the major scale in most keys, can only play in a few keys fluently,can play bass with left hand and chords with right,can barely hold down a service
advance-knows at least intermediate theory non traditonal scales, can play fluently in all keys,has a good chord vocabulary and knows when and not to use them,has been playing the keys more than 5 years minimum(even though some people been playing longer than 5 doesnt make you advance either), can transpose manually don't with a button lol understands how and when to use passing chords and notes
Pro-playing at least ten years, the same stuff as advance, can understand whats going on in a song without being at the piano, can improvise and/or arrange a song on to the keyboard from your head
thats my take on skill level i dont think the sick runs and chords dont make you advance or a pro its the technique, knowing your craft and how you fits those into the music your playing not just gospel but in other styles also.