Longer expiry time on visa

Hello , I am an Australian citizen and my wife a Chinese citizen, we have travelled to China 4 times in the last two years and each time I have to request a new entry permit and do the invite letter and copy forms and fill out the multi pages and pay again.
My question is :- Is the any way to get a multi entry one with a longer than 12 months expiry date?

US can get 10 years but AU can only get 12 months.
Thank you George