Hey Chris...... as others have mentioned I'm thinking that Bonaire would be an awesome trip for you and check all of your boxes......other than West Coast of USA!!Ah, I thought you did a pony from Dive Friends.
My point was more that @Cthippo , I believe, usually uses a pony but is not certified, so it would be difficult to rent one.
If you do happen to choose Bonaire I'd suggest staying at a dedicated dive op / resort like Buddy's or Captain Dons. Either of them can handle everything for you as a one stop shop. You can get unlimited shore diving "drive and dive" packages with a small truck rental, unlimited Nitrox (32)...etc. Both have full rental departments if you don't want to haul gear. You could also add in some boat dives with either of those ops. And, I would HIGHLY recommend at least one day with East Coast Divers.....guarantee you won't regret it!
As far as redundancy for solo goes, if you do decide to haul gear....... you can bring along a pony and transfill whip to eliminate any concerns about renting / filling. I dive a backmount pony with the Quickdraw mounting system which makes it simple to swap out main tanks. For Bonaire, since all of my diving is basically inside my self imposed MOD of 100ft, I bring my 13CF AL pony. Knowing that you are tolerant regarding water temps I think you'll be totally fine in just a rash guard top and board shorts...... That's what I use in Bon.
Last but not least..... you might also consider making a Bonaire trip an opportunity to complete the SDI Solo cert. Could not be any easier. I did mine at the SDI / TDS center at Captain Don's with Brian. Highly recommend.... Check out post No. 70 in the thread below for more details. Takes just one day of your trip and two dives as long as you've already completed all the academics ahead of time........and the dives are great dives! Included in the course, Brian will set you up with a sidemount / slung 40cf and reg-set and you'll get your actual solo card printed and issued same day once you've passed.
SDI specialty training for solo diver
My daughter's open water course last year, a university NAUI course, taught buddy breathing. Personally, I think buddy breathing is a valuable skill to have, another option divers "should" have in their toolbox. Just in case. rx7diver NAUI, nuff said
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