Some thoughts:
1) You don't need two rigs. Your BP/wings setup is GREAT! You'll enjoy the heck out of it, no matter how recreational you choose to dive. Keep it, use it, and learn to use it well.
2) You seem to be confusing the terms "stroke," "non-DIR," and "unsafe." "Stroke" is simply synonymous with "unsafe diver." "Non-DIR diver," however, does not necessarily imply "stroke."
My girlfriend is not DIR, and she's not terribly skilled either. Should that stop me from diving with her? Of course not. I only have to adhere to the following bits of common sense:
a) Ensure that we don't dive beyond her abilities, since she is the more novice diver. We generally do shallow shore air dives, use computers, and just have fun playing with seals and sailing through kelp and such. It's a great bonding experience, and no one, not even GI3, could convince me it's bad practice to dive with her.
b) Make efforts to improve obvious safety problems in technique, gear selection, and gear use. This doesn't mean I should throw her entire kit into the dumpster, buy her a BP, and send her to GUE DIR-F. Instead, this means that I should help make sure her equipment is set up properly, give her guidance on how we'll solve the type of problems we anticipate on our dives, do basic safety drills with her, and instill in her an awareness of the possible failure modes of our gear and our abilities.
The reason the DIR militants are so militant is simple: DIR is very safe, and most other systems are less safe. Please note the strong qualifier: most. In general, those that do everything their own way, without any regard to the opinion of those more experienced than themselves, tend to be somewhat unsafe -- but there certainly are those intelligent folks who blaze their own trails, and do so with safety on par with that of the DIR system. My hat is off to those people. They are quite rare.
It's often stunning to me to see all the belly-aching that goes on with regard to diving gear and technique standardization. Many other sports have such standardization clearly included as part-and-parcel of the sport itself. Rock climbing folks, for instance, have zero tolerance for others who, for instance, use their own knots, or their own anchoring techniques. There's really only one kind of gear to purchase, and one way to solve each problem, and no one questions any of it. Why not? Because the gear and techniques solve all problems with little, or at least predictable (thus manageable) risk. There isn't a single good reason to go against that dogma, because any differences are almost certain to decrease safety, rather than increase it. The same concept applies, with the same gusto, to diving: those who do everything their own way are seldom as safe as those that go with the collective choices of a large number of more experienced people.
- Warren