Gearing: with a standard secondary ratio of 18:53 my 72 turns at just about the same speed in top as my 95 Daytona. This is considered a very low gearing in our Brit Bike world, were we habitually compare with Norton Commandos, Bonnevilles and such like. In my view the Triple should be regarded as a very different design approach, much more modern if you will. The Triple enjoys being revved, and those who find that difficult to adjust to, should perhaps consider trading the bike for something else.
AM vs HDM heads: The HDM usually appears better cast. My Trident wears an AM head, and apart from some rough and porous spots in the casting, the chambers and ports are fine. The center exhaust port was a bit smaller than the outer two, so I enlarged it some, but keep in mind that the outer ports are overly large, so there's no reason to overdo it. A friend has a 74 with an AM head, on which the center port is even smaller than mine was, but his bike doesn't lack any performance at all, in fact it goes very well. In real life I don't think there's much in it, but since they saw fit to issue a service note on it, there must have been some heads worse than others I suppose.
A comment on exhaust ports: Old school ports were big, followed by a large diameter pipe, to aid rapid scavenging.
Modern thinking is a small diameter, short port, exposing far less surface area to absorb heat. The exhaust pipe is stuck as close to the valve as physically possible for the same reason. Our triples have large and long ports, further compromised by the screw in adaptors. Machining the exhaust ports to take push-in pipes ala BSA and the T140 would possibly help reduce cylinder head temperatures on our bikes. Better still if we could leave a gap between the casting and the pipe, as on many modern designs. I've been thinking along those lines for a while, and have a spare head to experiment with. Maybe one day...