Scott, calm down. You are not under attack here.
The chord issue is really much more simple than you portray. Remember, these keyboards are only trying to accompany the player, and I don't think they will ever be able to fully please all players.

Full mode works very well in most kb's to supply the band when all you add is two handed chords - it is not designed to "interpret" or "organize" your own particular styles of play. They take the notes most common to a chord and produce a backing. If you want to get fancy - you NEED to split the keyboard, so it can ignore the right hand when making chord changes.

Most people are not willing to let the automation software "lead" the band (so to speak) but you MUST.
The keyboards will NEVER really follow us - we just nudge them in the right direction, and then WE MUST FOLLOW the leader. Simple. The KB is the boss.
We are the ultimate organizer, but once you hit start - you have to follow what it gives you or YOU are wrong. It can't compensate for small nuances or odd fingerings. It only knows what it was programmed to know. It's NOT a player - it's a tool, and they all have limitations.
(like REAL players!)

I strongly suggest that you contact all your favorite companies and apply for a job in R&D so you can have one built that will please you, because that is the only way you'll get what you want..................
until the next thing changes, then you start over.

People - please remember that these kb's are filled with "workarounds" and compromises - learn the tricks and use the tool as best it can be used. The best way to enjoy the benifits of a particular tool is to work within it's strengths. Auto arranger keyboards is NOT the next art form - it's a shortcut to an end product that requires less people, less space and less money spent to acheive the goal...music.

Once again - Scott this is not an attack. You are a methodical, studious person and I don't mean to criticize that. I only stress that you seem to expect too much from an instrument that is clearly designed to a job that pleases MOST of the masses. Serious students of music, or players that use substituted chords must expect shortcomings from electronic intelligence. They simply cannot think like a real live player in every situation.
If you remember the compromises and play within the limits, you can get great results from these keyboards.
If you insist on your "particulars and nuances" - you'll need to sequence more, or reach in your pockets and pay some live players to get those results.
Auto arrangers are at the top of their game right now, and getting better all the time - let's not get ahead of what they can do. Enjoy the product that works now.
If you need to get "artsy" do it on a real intrument, and save the electronic toys for the paying gigs. They make life sooooo easy if you use them in context.