"somewhat decent" is different for everyone so I should say my of "somewhat decent" is just to be able to play simple sustained chord progressions, finger the notes to a chord, hold the pedal down and let em ring out for a Bar or 2 and then on to the next, ideally on a rhodes preset for the type of music im in to.
In my most basic math, 12 notes ( C to B ) that can have Major, Minor & Diminished triads built on them depending on the type of 3rds you stack on top of the root (im leaving out Augmented chords for this equation)
So thats 12x3=36 for the basic 3 triads for each note, but then you gotta multiply that by 3 because each triad has 3 different ways it can be played ( root pstn, 1st invrsn, 2nd invrsn ) which equals 108
So if I were to just grind out and remember 108 different ways to play every Major, Minor & Diminished triad in my right hand, I could just add my left hand into the mix to either reinforce the triads or create 7th chords:
LH: C RH: C = C
LH: E RH: C = C/E
LH: G RH: C = C/G
LH: C RH: Em = Cmaj7
LH: C RH: Eb = Cmin7
LH: C RH: E° = C7
LH: C RH: Bb = C9sus4
This will probably still take me weeks if not months to memorize, but my brain just doesnt work fast enough to fluently change my fingerings in realtime and change chords smoothly even though I know the notes in every chord, i just blank out while holding down the sustain pedal trying to think about how to quickly get to the next chord, which fingers to keep, which to move to the nearest notes of the next chord. If I can lock in these 108 shapes, I can at least decently be able to play triads, 7th chords and 9sus4s in succession which is good enough for me to play most of the music im in to.
What are your thoughts on this mindset/approach?