I thought I would add the perspective from a ground crew person:
When rotortuning Chinooks we originally wore our denims and used GC headsets. Good old Health & Safety came along
and made us wear flying kit. I was lucky enough to get the full nine yards including knife and flying jacket, I have to admit even without badges it was better than our denims, lots of cubby holes and pockets to lose pens and things in, two knee pads to scribble on and a proper helmet to strut around the flight line with. Great on detachments being initially treated as aircrew, soon got dropped a peg or two when they realised. The best bit was when I got posted to St Athan, an order was put out that unless you were authorised nobody could wear the flying jacket, which meant a lot of officers (not ex or current aircrew) had to stop wearing theirs, me I was still allowed to wear mine, that is untill a certain person got upset and had all my kit removed from me, it was fun while it lasted. As far as badges go I think it is up to each individual to decide what is acceptable to them, after all we are supposed to be grown ups with minds and thoughts of our own, not drones.