Well, I finally decided on a American Standard "Reliant" model4205.001.002 in polished Chrome. It has the traditional hot and cold feeds ("city shanks") at the outside of the base plate. This is how the current faucet is set up, greatly simplifying installation, which took an hour. The feeds are made of brass.
This faucet works quite well, with a spout an inch longer and an inch higher than the old faucet. It is also a factor of 1.67 heavier, far more than expected from the slight increase in spout length. The new faucet cost $100 delivered from Faucet.com.
The old faucet was an American Standard "Cadet" model 8411F, in polished Chrome, for $60 or so from Home Depot. The spout leaked from a pinhole in the bottom side of the spout tube, and from the rotating seal at the base. The rotating seal had been leaking for some time, undetected. This after only 2.5 years, far too short.
First, the old spout. I sectioned it with a bandsaw. It turns out that the spout tube is made of sheet brass 0.032" thick. There is a lengthwise seam along the bottom of the spout, and this seam was not fully formed or sealed, and the pinhole formed in the seam about three inches from the hub.
There is no sign of solder or braze metal along the seam, although the tube appears to be brazed to the hub. The tube may have been welded, as there was some "burr" (weld flash?) along the seam. One can see the seam crack along parts of the bottom of the spout, right through the chrome plating, and one assumes that these places would soon have sprung a leak as well.
The new spout is made of "cast brass", while the old spout is made of "brass", according to the spec sheets. The cast brass spout may account for the increased weight - walls will be thicker, and there will be no seam. By my measurements, the new faucet weighs 5.5 pounds, while the old faucet weighs 3.25 pounds, the difference being 2.25 pounds, which is plausible for the spout.
Now, the old rotating seal. Although water dribbled out from between the hub and the post upon which the hub rotates, it turned out that the two big greased rotating O-ring seals were not the problem, despite appearances.
What had happened was that at least one seal inside the post leaked. The leak happened only when the faucet was on, so the leak had to be from the spout-feed part of the valve, not the hot and cold inlet parts. The valve is a ceramic-disk type, and works perfectly. The post is made of multiple pieces of brass and nylon held together with three stainless steel machine screws, and things were pretty corroded inside, in places that should not be corroded. I recall seeing some drops of water when I first installed the old valve (which little leak went away soon thereafter), so I bet this always leaked.
The seal that leaked is a rubber tube stub in a tight-fitting channel (made of nylon) and compressed lengthwise. The tube stub is 0.500" in diameter, 0.25" long, with walls that are 0.067" thick, and is made of a fairly stiff kind of rubber. This stub tube didn't seat correctly, for some unknown reason. The design is not pressure-activated, unlike an O-ring. The new faucet appears for the parts diagram to use only O-rings. I bet I can guess why.
I think I'll complain to American Standard. This ought to be amusing.