My Casio PX360 is 26 pounds and I am looking to get a lighter model with the new casios. A 73 key Casio with an aluminum base, onboard monitors, that weighs ~ 19 pounds would be awesome.
You might be interested in checking out the CDP-S350, although it’s 88 keys, not 73. You can download the manuals for it from Casio’s web site, although I don’t think it’s been officially unveiled yet— any day now, though!
Looks like no MIDI DIN ports, if that matters to you; and polyphony is a bit low for a digital piano— 64 notes, 32 for certain tones. But it has a goodly number of tones, and responds to MIDI messages for Attack/Release, Cutoff/Resonance, Portamento, etc., so I’m definitely interested in giving it a hard look.
CDP-S350 video from Jeremy See showed up in my news feed. Not terrible.