Well, for live gigging to be only OMB, that sure discounts a lot of other ways to gig!
But now you have narrowed it down to a better defined goal, you are STILL basically getting 'Use what I use!' from everyone. Thing is, none of us would buy what WE thought was less than the best for what we need, but mysteriously, most of us manage to use different gear. Perhaps we have different ideas of what IS 'best'?

Your initial post recognized how this was nothing but an excuse for a pissing contest (and yet, apparently,
I am the one dragging this forum down

), and here we are. Surprise, surprise!
Look, I'm in my mid-50's. Weight does affect me. But so does less than stellar sound. I carry my arranger for a couple of minutes a day. I play it for HOURS. I can appreciate weight being a consideration if you are infirm, but there are plenty hale and hearty here that seem to be able to lug around fifty pound speakers but blanch at the though of an arranger lighter than that!
Stairs, Ian, are not that big a deal, especially in the Gulf Coast, where everything gets wiped out and rebuilt every few years thanks to those nice hurricanes... The handicap access laws have made ramps and elevators far more common than they may be where you work. I also, especially this year, find myself playing live a lot more (in the sense of 'without a machine') so if something comes up that is tough for me, I get a bit of help. But, push comes to shove (pun intended!) I have never found a place where I couldn't get the beast into.
Perhaps they COULD make something at the level of quality and touch I prefer at under 30 lbs., but I haven't found it yet. To a certain degree, rigidity and solid actions come at a weight penalty, unless you are prepared to pay a fortune for exotic composites like carbon fiber... The real estate of arranger layout makes them a LOT larger than the stripped down sizes that pianos can be, meaning that they will be heavier.
But if you take a look at pro WS's, you'll find a large number of them over your weight limit, and many that dwarf my G70! If PSR touch and construction are sufficient for you, you'll be fine. But at least let those of us that DO prefer better than that put up with the additional weight that that entails. Strokes for folks, and all that. I don't look forward to the day that ALL arrangers are made as flimsy as PSR's, just to keep the senior citizens happy.