Update:

The springs ARE pretty light, but not as light as my wife's SP-101 with the 9lb wolff kit. Firing pin protrusion is ample, barely clears the cylinder face. The tip of the pin looks fine, can even still see the machining rings around the tip (i.e. not worn).

I checked the timing on the revolver and it was "slow" on one cylinder, about a 50/50 whether it locked up before the hammer break or not. The alignment is fine upon lock-up, it was just not quite locking up (way too late regardless).

I noted that a few of the teeth on the extractor were dinged (not sure how that would have happened to this extent), including the one for the late cylinder, so I got pretty concerned at that point.

So since I had it in hand, I disassembled everything and cleaned it throroughly. The tip of the hand appears chipped/worn. The hand and the extractor were badly fouled, but nothing some solvent and elbow grease didn't work out.

Upon reassembly, after taking all of the gunk out of the extractor and off of the tip of the hand, I somewhat expected what happened next. Now ALL of the cylinders are late, about 50/50 whether the DA hammer breaks before or after lock up. SA locks up just before full cock, not as early as I would like, but it's positive lock-up every time.

Alignment is fine once it's locked up.

So all in all, sounds like good news. The hand is easy to replace, and cheap. Replacing the extractor on taurus's means returning to the factory for a new cylinder (or buying a used cylinder), but since ALL chambers appear equally late, if I can get a new hand that's not chipped and worn, we'll be back in business.

So I ordered a new hand from Taurus, should be here by the end of the week (supposedly). $12 to my door, would have been free under warranty if I mailed it to them, but I figured it'd cost me more than $12 and 20min of my time to ship them the revolver.

If the new hand doesn't work (i.e. isn't long enough), I'll be doing a weld and reprofile job to extend the new factory part. Judging by the tip of the hand, I'm betting the new one will be longer and not chipped, so my money says it's going to remedy my problem.