What u all r calling churchy is a gospel sound called black gospel or southern gospel. The style is different as it uses non traditional voicings. It gets pretty deep but if you want to play like that you could buy his material at
www.hearandplay.comHe uses alot of dominant sevenths and open voicings. For instance insted of playing a C7 flat out play a C octave in your left hand and a Bb chord in your right hand. This really makes it an eleventh but every time you see a dom7 you can do this; just play the root in the left hand and a major chord 1 wholestep lower in your right hand.
Or u could play an octave root in the left and a major chord a 5th above the root in the right hand so u would have an octave C in left and a G major in the right. You can then invert it however u want.
These examples will give u a more modern sound. Alot of what u heard in that clip sounded like minors and sevenths with some substitutions.
Try playing it like this 2-5-1
Dmin7 (root)
G7 (2nd)
Cmaj7 (root)
Or play it with a substitution such as this 2-5-1
Dmin7 (root)
D7
G7
The D7 here serves as the dominant chord to the G7, use the inversions that r eaisest to transfer to.
Or u could play it like this 2-5-1
D7 (root)
G7 (2nd)
Cmaj7 (root)
So far all these progressions use the root as base but this next one is different
F#dim7/D
Fmaj/G
Cmaj
If u want it happier change the F#dim7/D to F#half diminished instead.
There r tons of 2-5-1 progressions u can do. You can take these and get a similiar sound by adding passing tones and some patterns to your left hand as well as break up the chords in your left hand. Think outside the box when u break chords up. We often play the chord from the bottom to the top or top to bottom. On sevenths u have four notes, u can play the root and seventh together and then hit the 3rd with your fifth below it. This is a nice sound if done right but it is hard for me to explain on here.
Another way of breaking your sevenths up is to play it like this:
C7= Root, Fifth, High root for left hand
then g-up to the c, down to the b, and back to the g and of course the pedal is held down. This is a modern voicing but it gives u the idea. I am just trying to spark some creativity. u should be able to find a churchy 2-5-1 out of the above examples and then just spread the chords out amongst the left and right hands and play some easy fill in patterns.
That churchy sound relies on the blues, incorporate some bluesy chords and open blues voicings into your playing and u will be on your way.
I have only been into it for the last 5 months so I still have a lot of learning to go and am still only messing with the basics. Prior to that I had about two years of classical sight training (bla, bla, bla, no fun) and threw the notes down to learn to play by ear.
As far as the practise questions that is difficult. I have been taking notes for a couple of weeks on practice material as I needed a good plan to follow. I heard it said like this: Its not practice that will make you perfect but perfect practice. It is like lifting weights, if u want to get huge and ripped u have to have a plan. It can not be hit and miss or a little of this today and some of that tomorrow. You have to formulate a plan that will attack the areas u r lacking and stay up to speed on stuff u r good at as well as challenge yourself to experiment with new ideas and even accomplish some just for fun playing.
I am still researching and will post my piano workout in a simplified form when it is finished. Hopefully I will get most of it down on paper tomorrow.
I hope I helped someone. Have fun and do some perfect practice.