I think you're barking up the wrong tree entirely. At minimum, you ougthta stop casting aspirtions at people with phrases like "turn up their nose" or "too rigid" or "dogma." From a marketing standpoint, you're the one being "too rigid" and the one who is "turning up their nose" at the preference of people who you seem to think are your customers. Smart marketing starts with considering who is your target audience, within the total universe, that has a need that your product meet, and then delivering your product to that target audience. Poor marketing starts with someone having a product in hand, who then gets confused/mad/frustrated that it doesn't appeal to 100% of potential buyers.
As you said, single-tank recreational divers outnumber GUE/Tech/Doubles divers 100 to 1 --- so why on earth are you worried about getting your product to appeal to the 1 at the expense of the 100. From a marketing perspective you've got a product that is differentiated entirely. From a positioning/target market perspective you've got a marketer's dream: A product that specifically and uniquely meets the need of a large segment of the audience. However you're making the classic marketing-amature mistake of trying to create a product that appeals to everyone. It's not possible. Even if it were possible, it's not desirable. (Hell, having the "GUE stamp of approval" would probably cost you more customers than you would gain given the disdain that many folks have for anything remotely DIR.
Think "un-cola" in this case. You've got the "un-plate" my friend! The Freedom Plate could be "the backplate for people who don't want the xxxxx of a backplate." (Whatever xxxxxxx may be, you've "freed" divers from that.) That's a much better positioning than being "a lesser backplate that is potentially appealing to a subset of people who don't really like my product, and aready own several competitve products, but damn-it, I'm sure I can convince them they have an occasional need for mine."