Perks come and go and are not guaranteed. In addition to AP or a special restricted AP or ticket deals there are discounts at some restaurants and shopping. IMO the perks and discounts are designed to make you spend more not less. Disney gives you $100 off of an AP so now you vacation twice in a year instead of your normal once per year.
It's true that the perks associated with DVC can (and have) changed, so it's a good idea to consider them as gravy rather than consider them as a serious factor in a purchase. But that's not what you asked, LOL.
The most recent list of perks can be found on the DVC Members' website. For those who do not have access to that site, AllEars.Net has a good list and it also includes AP perks, which many DVC members also have :