First of all, kudos for your excellent buddy habits! Many problems can be minimized through frequent checks like those that you two employed.
One of the things that most bothers me about your trip to the Hole is that an inexperienced group of divers was left at depth without supervision. On an escorted dive, this is outrageous. Dive operators need to be prepared for an emergency or two on a dive like this one, and if they aren't, I wouldn't be following them anywhere.
My instructors were very conservative divers-- something I rarely hear about nowadays. But our dives were in very remote areas whether it was from the beach or a boat, and the only help we had within 100 miles was from each other. That made choosing the right buddy priority #1. Researching the conditions of the dive site was priority #1. And getting to know something about fellow divers on the boat (without actually drilling them about their experience level) was priority #1.
In addition, I was taught - and continued teaching the principle to my students - that lessons are best learned at depths of 20-40', and the best sea life is at or above 60'. We certainly dived much deeper but not without a reason.
You have good instincts; now hone your skills with additional controlled diving and training. In addition to Rescue, I highly recommend that you take the Equipment Specialist course, the Deep Specialty, and the Search & Recovery Specialty. All together, these will give you confidence and more skills to pull out of your pocket when the need arises... and believe it, the need WILL continue to arise as you rack up dives in international waters.
Other than recommending the above courses, my best suggestion is that when you travel by air and luggage space is at a premium, find room for your own mask, regulators and depth gauge/computer no matter what. You'll learn in the equip classes how to put together a large repair kit and another small one for travel. Rent tank, BCD and weights if you wish but when it comes to the things your life depends on underwater, put your faith in the gear you know and have maintained.