If you want 76 keys, your choices are slim, indeed. The BIG 3 becomes the Big 2 on this issue....!

If money is no object (or time - it won't be out for quite a while) that new Ketron Audya looks interesting.

If you can compromise about the weight (you may have to, there are only a couple of 76-ers in your stated weight limit) the G70 or PA1XPro are both good (in different ways.

If an older arranger would work for you, a G1000 is a good choice (and the Chord Sequencer is excellent for blowing solos on top of a head you just played).

But my advice would be to forget the weight issue (just get a very light case!) and give the G70 a hard look. Wonderful jazz styles, a killer grand piano sound, a killer key-bed, a killer B3 sound, and killer drums. Most of what you need for a jazz gig......