As my most excellent fishing partner, beer drinking, twin brother Dr. Peskoe would say: "That is freakin' brilliant. Brilliant I say." I did think of one other little piece of advice. When stripping your fly, lower your rod tip into the water. This dampens the wobbling rod tip and minimizes line slack. If your rod tip is above the water, your fly line will droop resulting in slack line between your stripping hand and your fly. This is bad for two reasons. One, when you attempt to make your next strip, you have to remove that slack before the fly will move. That means your fly won't be moving as much as you think it is. Second, if a tarpon suddenly pounces on your fly, you have to remove that slack before you solidly set the hook. Most of the time in fly fishing, slack isn't good. So keep your rod tip in the water while stripping your fly.
I think your most important piece of advice is the one on casting. Many anglers forget to haul on their forward casts. They'd make great false casts but on the actual presentation cast they'd slow down the rod and not haul. I really think having the ability to cast a solid 80feet of line allowed me to reach more fish this last trip. Especially on the outside flats and in the rio mouths. Being able to reach them before they sense the boat I think increased the number of takes I got. Being able to shoot a narrow tight loop up into a rio mouth before the pressure wave from the boat reaches it helped get a take. Once those fish sense the boat coming they move up the rio.
Casting practice is a good idea for all of us. If you haven't been out double hauling your 8 wt in last month, it may be very productive to get out and do a little practice before your trip. Stand on a milk crate in an open field or on the shore of a pond if your lucky enough to have one. Pick a target, a floating leaf or twig, or something, and try to hit that target with a minimum of one or two false casts, Vary your targets, you don't often get several repeat casts at moving tarpon. The first one is the money maker so make it your best. It isn't as productive to make several casts at the same target getting the range and haul correct on the second, third or fourth try. You need to be able to do that on your first try.
I don't know the best answer to this one but I spooked several fish when I cast to a fish I saw and didn't see the ones closer to me. I lined those fish and they spooked everything. Obviously if you don't see the closer fish and the fish you did see is quickly going out of range you're at a point of no return - it's fish or cut bait time. But sometimes it pays to observe for a few extra seconds and look for fish between you and the ones you see. Or even make a shorter cast and retrieve first before making the home run cast. I dunno.
It also pays to observe the direction and speed of the fish. Most tarpon, especially on the outside flats are cruising. If it takes you a false cast or two to present the fly, that fish could have moved 10 feet or more easily. If you cast to where you last saw it, you'll be 10 feet behind it and most tarpon aren't going to turn around to eat a fly. The wind plays into this strategy as well. You sometimes need to gauge windage and apply a little fudge factor to make sure your fly lands 3 - 6 feet in front of the tarpon.
Oh that reminds me of another one. I call it "happy feet". Try to establish a comfortable stance on the deck once you've stripped off your line and gotten situated. Anticipate the direction you'll be casting if possible, e.g. which side is the shore on, or which direction is the wind from, or where is the deeper water in the rio mouth. Once you get your feet set, try your darndest not to move them. Moving around on the casting deck causes all kinds of potential problems. From stepping on your line, to rocking the boat unnecessarily which alerts fish to your presence, causing your guide to have to reposition him or herself on the poling platform, etc.