"Be afraid; be very afraid"
There have already been a number of weight increases over the last two decades. The last one was from 544 to 600 kg, a little more a ten per cent increase. An increase from 600 kg to 750 represents a further 17 per cent increase. This is almost a 30% increase over 544 kg. By this time, the laws of physics determines that an incident is likely to lead to bigger injuries or more frequent loss of life. What is the real purpose of the RA-Aus asking for this? Is it some kind of Empire Building, a way to increase the numbers of aircraft on that register rather than the VH register?
Picture this: once the 750 kg limit has been approved, I think we'll have a flood of ex-VH aircraft joining the RA-Aus register. Most of these are from the 1940s, 1950s and 1960s; some are from the 1970s and 1980s. Whichever way you look at it, they are old aircraft, pretty much close to the end of their useful lives. The current RA-Aus register would have very few aircraft of that vintage. Some of these older aircraft may fall out of the sky (God forbid!) and that will lead to undue attention on RA-Aus. This is likely to result in a media call to "do something" and demand "tighter restrictions on those ultralight Cessnas" or words to that effect. The final outcome may indeed mean that the aviation-ignorant legislators feel that they need to satisfy the media demands and actually impose a stricter regime on all recreational aeroplanes.
Is this worth it? What do the majority of RA-Aus members actually want?