Hey Ray, I've lived on Utila since Sept 2011 and have dove Roatan a few times but never Guanaja. For your particular situation, having been to Utila already, I would recommend Guanaja. Guanaja is as pristine as you're going to get anywhere near here. From what my buddy says, it's like diving Roatan and Utila 50 years ago. It's much less impacted by people.
Coincidentally, my buddy and I were working on putting together a package deal, before he left for Isreal, for people exactly like you've described yourselves...adventurous backpacker diver types who are used to camping and looking for an unforgettable experience. Guanaja used to be a thriving place built for mainly rich drug dealers, so the story goes, until a storm destroyed the resorts. Aftr that nobody went back to rebuild and Guanaja is now a very pristine ecosystem.
One of my good friends' father, who is also a friend of mine, owns and operates Island Air here in the Bay Islands. His son, Angelo Lagonia Jr, and I came up with an idea to offer he most unique, once in a lifetime type dive experiences. Since Guanaja is as gorgeous as it is and their family used to own property on Guanaja and still have good connections out there, we decided to figure out how to create this service. We got so far as to designing a website and woring out most of the costs to do different custom package deals.
Our idea was to fly one of us, as Divemaster and liaison, along with the clients out to Guanaja, meet up with one of the local guides who are old friends of the family, so trustworthy, ride horses up to the big mountain to a campsite where we would do hikes, when not diving, to see the local points of interest, then down to the dive shop via horse for some diving (Camping Package). Food could be brought to the campsite every day and even have it prepared for you at the campsite if you like. We would be very flexible and work 100% for you to leave this vacation feeling you just robbed us in the deal, lol. Whatever you want in a dive vacation is what we will work towards. If you wanted a roof over your head (House Package) there is a house we could stay in near the dive shop. If you needed dive gear we could rent it from one of the dives shops I work with for better than average prices around here. If you wanted to go along on a lionfish hunt, we can do that and you can enjoy the meat over a campfire or served to you at a table. The idea was to tailor the best, most unique experience possible with the unique connections we have there.
We didn't move forward with the idea because, Angelo Jr moved to Isreal on fairly short notice and we never made it over there for me to meet the locals that are friends of the family and would be the local guides. I do have pictures and an almost complete price list that could offer us a fair idea of how much a package deal like that would run you.
One thing is for sure, with these unique connections, I can offer you the best Guanaja dive vacation possible. Bar none! If tht sounds like something you would be interested in, drop me a PM or message me on FB and we can work something out for you. I'm KellyThe LionfishHunter on FB and cofounder of World Lionfish Hunters Association. Either one of those would work just fine.