My main beef with all of the Casios is that they lack any kind of sync stop, arranger hold setting, memory, or "stop accompaniment" function for playing rubato with chords and auto bass.

Feature-wise the much better option is an 88-key piano controller MIDI'd to an arranger module, or mounted organ-style just below the keybed of a current MOTL arranger.

I admit i've been looking at Clavinovas and even the Kohler KD-60 (which is a Korg Pa80 in a furniture cabinet.) These are fully-featured arranger pianos. But they aren't even close to being portable!