Welcome to LGM, Jtabije! It takes courage to break out of one's mindset to learn something new.
As you know, Contemp. and Traditional Gospel chord progressions are related to Jazz/Blues/NeoSoul, so listening to any of that is good. As for voicing, that depends on the ensemble, a solo player would play more fully than someone in a praise team with bass, guitar, etc. But I notice that contemp. Gospel keyboard players often use mid-range rootless voicings, sus/9th/11th/13th/altered Jazz chords and tritones for the bottom two notes in the LH. They also do lots of runs in between the vocal lines (something I haven't mastered yet).
And you are right about Chord substitutions - most CCM chords can be "Phattened" up by making the chords more complex - listen to a song like "Lord Prepare Me" by West Angeles COGIC (based on the old praise song "Lord Prepare Me to Be a Sanctuary")
a video tutorial -
(I got the sheet music for this arr. from ntime music)
If the chord is -
CCM Jazz/Gospel - add...
Major ----> Major 6th, 7th or 9th
Minor ----> Minor 6th, 7th, 9th
SUS ----> add 7th, 9th, 11th (this will often result in a bitonal or "dual-chord" voicing like Bb/C, etc.)
dim ----> dim 7th, or the half-diminished m7th, like Cm7 (b5) = C Eb Gb Bb
Aug ----> any kind of whole-tone alteration - like adding a m7
Something else these cats do is a lot of Chromatic movement - instead of doing a standard C - F or a guitar-style walkdown like C G/B Am Am/G F, they will often do something like C2 Gb9 F69...
As for how to learn this - what is your learning style? By ear or by note? If you can read music, you can find printed gospel sheet music at
www.ntimemusic.com, and also some "How to play Gospel" type books.
If you go more by ear, you can check out Gospel and Jazz tutorials on YouTube, get one of the DVD courses by Hear and Play or Wheatworks, or just stick around here, there are lots of resources. SoundOfJoy has some videos, and also has a free online course. T-Block has a sticky posted with lots of chorded (spelled out chords w/lyrics) songs....